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Wang L, Chen CC, Zhang Z, Kuo HT, Zhang C, Colpo N, Merkens H, Bénard F, Lin KS. Synthesis and Evaluation of Novel 68Ga-Labeled [D-Phe 6,Leu 13ψThz 14]bombesin(6-14) Analogs for Cancer Imaging with Positron Emission Tomography. Pharmaceuticals (Basel) 2024; 17:621. [PMID: 38794191 PMCID: PMC11124507 DOI: 10.3390/ph17050621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Revised: 05/05/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024] Open
Abstract
Gastrin-releasing peptide receptor (GRPR) is overexpressed in various cancers and is a promising target for cancer diagnosis and therapy. However, the high pancreas uptake and/or metabolic instability observed for most reported GRPR-targeted radioligands might limit their clinical applications. Our group recently reported a GRPR-targeted antagonist tracer, [68Ga]Ga-TacsBOMB2 ([68Ga]Ga-DOTA-Pip-D-Phe6-Gln7-Trp8-Ala9-Val10-Gly11-His12-Leu13ψThz14-NH2), which showed a minimal pancreas uptake in a preclinical mouse model. In this study, we synthesized four derivatives with unnatural amino acid substitutions (Tle10-derived Ga-LW01158, NMe-His12-derived Ga-LW01160, α-Me-Trp8- and Tle10-derived Ga-LW01186, and Tle10- and N-Me-Gly11-derived Ga-LW02002) and evaluated their potential for detecting GRPR-expressing tumors with positron emission tomography (PET). The binding affinities (Ki(GRPR)) of Ga-LW01158, Ga-LW01160, Ga-LW01186, and Ga-LW02002 were 5.11 ± 0.47, 187 ± 17.8, 6.94 ± 0.95, and 11.0 ± 0.39 nM, respectively. [68Ga]Ga-LW01158, [68Ga]Ga-LW01186, and [68Ga]Ga-LW02002 enabled clear visualization of subcutaneously implanted human prostate cancer PC-3 tumor xenografts in mice in PET images. Ex vivo biodistribution studies showed that [68Ga]Ga-LW01158 had the highest tumor uptake (11.2 ± 0.65 %ID/g) and good tumor-to-background uptake ratios at 1 h post-injection. Comparable in vivo stabilities were observed for [68Ga]Ga-LW01158, [68Ga]Ga-LW01186, and [68Ga]Ga-LW02002 (76.5-80.7% remaining intact in mouse plasma at 15 min post-injection). In summary, the Tle10 substitution, either alone or combined with α-Me-Trp8 or NMe-Gly11 substitution, in Ga-TacsBOMB2 generates derivatives that retained good GRPR binding affinity and in vivo stability. With good tumor uptake and tumor-to-background imaging contrast, [68Ga]Ga-LW01158 is promising for detecting GRPR-expressing lesions with PET.
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Affiliation(s)
- Lei Wang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
| | - Chao-Cheng Chen
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
| | - Chengcheng Zhang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
| | - Nadine Colpo
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC V5Z 4E6, Canada
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
| | - François Bénard
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC V5Z 4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada; (L.W.); (C.-C.C.); (Z.Z.); (H.-T.K.); (C.Z.); (N.C.); (H.M.); (F.B.)
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC V5Z 4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
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Hou H, Pan Y, Wang Y, Ma Y, Niu X, Sun S, Hou G, Tao W, Gao F. Development and first-in-human study of PSMA-targeted PET tracers with improved pharmacokinetic properties. Eur J Nucl Med Mol Imaging 2024:10.1007/s00259-024-06726-6. [PMID: 38683349 DOI: 10.1007/s00259-024-06726-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 04/21/2024] [Indexed: 05/01/2024]
Abstract
PURPOSE A series of new 68Ga-labeled tracers based on [68Ga]Ga-PSMA-617 were developed to augment the tumor-to-kidney ratio and reduce the activity accumulation in bladder, ultimately minimize radiation toxicity to the urinary system. METHODS We introduced quinoline group, phenylalanine and decanoic acid into different tracers to enhance their lipophilicity, strategically limiting their metabolic pathway through the urinary system. Their binding affinity onto LNCaP cells was determined through in vitro saturation assays and competition binding assays. In vivo metabolic study, PET imaging and biodistribution experiment were performed in LNCaP tumor-bearing B-NSG male mice. The most promising tracer was selected for first-in-human study. RESULTS Four radiotracers were synthesized with radiochemical purity (RCP) > 95% and molar activity in a range of 20.0-25.5 GBq/μmol. The binding affinities (Ki) of TWS01, TWS02 to PSMA were in the low nanomolar range (< 10 nM), while TWS03 and TWS04 exhibited binding affinities with Ki > 20 nM (59.42 nM for TWS03 and 37.14 nM for TWS04). All radiotracers exhibited high stability in vivo except [68Ga]Ga-TWS03. Micro PET/CT imaging and biodistribution analysis revealed that [68Ga]Ga-TWS02 enabled clear tumor visualization in PET images at 1.5 h post-injection, with higher tumor-to-kidney ratio (T/K, 0.93) and tumor-to-muscle ratio (T/M, 107.62) compared with [68Ga]Ga-PSMA-617 (T/K: 0.39, T/M: 15.01) and [68Ga]Ga-PSMA-11 (T/K: 0.15, T/M: 24.00). In first-in-human study, [68Ga]Ga-TWS02 effectively detected PCa-associated lesions including primary and metastatic lesions, with lower accumulation in urinary system, suggesting that [68Ga]Ga-TWS02 might be applied in the detection of bladder invasion, with minimized radiation toxicity to the urinary system. CONCLUSION Introduction of quinoline group, phenylalanine and decanoic acid into different tracers can modulate the binding affinity and pharmacokinetics of PSMA in vivo. [68Ga]Ga-TWS02 showed high binding affinity to PSMA, excellent pharmacokinetic properties and clear imaging of PCa-associated lesions, making it a promising radiotracer for the clinical diagnosis of PCa. Moreover, TWS02 with a chelator DOTA could also label 177Lu and 225Ac, which could be used for PCa treatment without significant side effects. TRIAL REGISTRATION The clinical evaluation of this study was registered On October 30, 2021 at https://www.chictr.org.cn/ (No: ChiCTR2100052545).
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Affiliation(s)
- Haodong Hou
- Key Laboratory for Experimental Teratology of the Ministry of Education and Research Center for Experimental Nuclear Medicine, School of Basic Medical Sciences, Shandong University, No. 44 Wenhua Xi Road, Jinan, 250012, Shandong, China
| | - Yuan Pan
- Key Laboratory for Experimental Teratology of the Ministry of Education and Research Center for Experimental Nuclear Medicine, School of Basic Medical Sciences, Shandong University, No. 44 Wenhua Xi Road, Jinan, 250012, Shandong, China
| | - Yanzhi Wang
- Key Laboratory for Experimental Teratology of the Ministry of Education and Research Center for Experimental Nuclear Medicine, School of Basic Medical Sciences, Shandong University, No. 44 Wenhua Xi Road, Jinan, 250012, Shandong, China
| | - Yuze Ma
- Key Laboratory for Experimental Teratology of the Ministry of Education and Research Center for Experimental Nuclear Medicine, School of Basic Medical Sciences, Shandong University, No. 44 Wenhua Xi Road, Jinan, 250012, Shandong, China
| | - Xiaobing Niu
- Department of Urology, The Affiliated Huaian No. 1 People's Hospital of Nanjing Medical University, No. 1 Huanghe West Road, Huai'an, 223300, Jiangsu, China
| | - Suan Sun
- Department of Pathology, The Affiliated Huaian No. 1 People's Hospital of Nanjing Medical University, No. 1 Huanghe West Road, Huai'an, 223300, Jiangsu, China
| | - Guihua Hou
- Key Laboratory for Experimental Teratology of the Ministry of Education and Research Center for Experimental Nuclear Medicine, School of Basic Medical Sciences, Shandong University, No. 44 Wenhua Xi Road, Jinan, 250012, Shandong, China.
| | - Weijing Tao
- Department of Nuclear Medicine, The Affiliated Huaian No. 1 People's Hospital of Nanjing Medical University, No. 1 Huanghe West Road, Huai'an, 223300, Jiangsu, China.
| | - Feng Gao
- Key Laboratory for Experimental Teratology of the Ministry of Education and Research Center for Experimental Nuclear Medicine, School of Basic Medical Sciences, Shandong University, No. 44 Wenhua Xi Road, Jinan, 250012, Shandong, China.
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El Fakiri M, Ayada N, Müller M, Hvass L, Gamzov TH, Clausen AS, Geis NM, Steinacker N, Hansson E, Lindegren S, Aneheim E, Jensen H, Eder AC, Jensen AI, Poulie CBM, Kjaer A, Eder M, Herth MM. Development and Preclinical Evaluation of [ 211At]PSAt-3-Ga: An Inhibitor for Targeted α-Therapy of Prostate Cancer. J Nucl Med 2024; 65:593-599. [PMID: 38423784 DOI: 10.2967/jnumed.123.267043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 01/23/2024] [Indexed: 03/02/2024] Open
Abstract
The application of prostate-specific membrane antigen (PSMA)-targeted α-therapy is a promising alternative to β--particle-based treatments. 211At is among the potential α-emitters that are favorable for this concept. Herein, 211At-based PSMA radiopharmaceuticals were designed, developed, and evaluated. Methods: To identify a 211At-labeled lead, a surrogate strategy was applied. Because astatine does not exist as a stable nuclide, it is commonly replaced with iodine to mimic the pharmacokinetic behavior of the corresponding 211At-labeled compounds. To facilitate the process of structural design, iodine-based candidates were radiolabeled with the PET radionuclide 68Ga to study their preliminary in vitro and in vivo properties before the desired 211At-labeled lead compound was formed. The most promising candidate from this evaluation was chosen to be 211At-labeled and tested in biodistribution studies. Results: All 68Ga-labeled surrogates displayed affinities in the nanomolar range and specific internalization in PSMA-positive LNCaP cells. PET imaging of these compounds identified [68Ga]PSGa-3 as the lead compound. Subsequently, [211At]PSAt-3-Ga was synthesized in a radiochemical yield of 35% and showed tumor uptake of 19 ± 8 percentage injected dose per gram of tissue (%ID/g) at 1 h after injection and 7.6 ± 2.9 %ID/g after 24 h. Uptake in off-target tissues such as the thyroid (2.0 ± 1.1 %ID/g), spleen (3.0 ± 0.6 %ID/g), or stomach (2.0 ± 0.4 %ID/g) was low, indicating low in vivo deastatination of [211At]PSAt-3-Ga. Conclusion: The reported findings support the use of iodine-based and 68Ga-labeled variants as a convenient strategy for developing astatinated compounds and confirm [211At]PSAt-3 as a promising radiopharmaceutical for targeted α-therapy.
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Affiliation(s)
- Mohamed El Fakiri
- Department of Nuclear Medicine, University Medical Center Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Division of Radiopharmaceutical Development, German Cancer Consortium Partner Site, Freiburg, Germany
- German Cancer Research Center, Heidelberg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nawal Ayada
- Department of Nuclear Medicine, University Medical Center Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Division of Radiopharmaceutical Development, German Cancer Consortium Partner Site, Freiburg, Germany
- German Cancer Research Center, Heidelberg, Germany
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marius Müller
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
| | - Lars Hvass
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
- Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Teodor H Gamzov
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anne Skovsbo Clausen
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
- Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolas M Geis
- Department of Nuclear Medicine, University Medical Center Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Division of Radiopharmaceutical Development, German Cancer Consortium Partner Site, Freiburg, Germany
- German Cancer Research Center, Heidelberg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Nils Steinacker
- Department of Nuclear Medicine, University Medical Center Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Division of Radiopharmaceutical Development, German Cancer Consortium Partner Site, Freiburg, Germany
- German Cancer Research Center, Heidelberg, Germany
| | | | - Sture Lindegren
- Atley Solutions AB, Gothenburg, Sweden
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; and
| | - Emma Aneheim
- Atley Solutions AB, Gothenburg, Sweden
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; and
| | - Holger Jensen
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
| | - Ann-Christin Eder
- Department of Nuclear Medicine, University Medical Center Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Division of Radiopharmaceutical Development, German Cancer Consortium Partner Site, Freiburg, Germany
- German Cancer Research Center, Heidelberg, Germany
| | - Andreas I Jensen
- Center for Nanomedicine and Theranostics, DTU Health Technology, DTU, Lyngby, Denmark
| | - Christian B M Poulie
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark;
| | - Andreas Kjaer
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
- Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Matthias Eder
- Department of Nuclear Medicine, University Medical Center Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Division of Radiopharmaceutical Development, German Cancer Consortium Partner Site, Freiburg, Germany
- German Cancer Research Center, Heidelberg, Germany
| | - Matthias M Herth
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark;
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
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Gühne F, Schilder T, Seifert P, Kühnel C, Freesmeyer M. Dependence of Renal Uptake on Kidney Function in [ 68Ga]Ga-PSMA-11 PET/CT Imaging. Diagnostics (Basel) 2024; 14:696. [PMID: 38611608 PMCID: PMC11012145 DOI: 10.3390/diagnostics14070696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/21/2024] [Accepted: 03/24/2024] [Indexed: 04/14/2024] Open
Abstract
(1) Background: PSMA ligand PET/CT is increasingly important for diagnostics of prostate cancer and other tumor diseases. In particular, the radiopharmaceutical [68Ga]Ga-PSMA-11 is widely used. Besides its tumor-specific binding, the uptake within the kidneys is dominant and seems to visualize the renal cortex specifically. Kidney diseases may alter the uptake of radiopharmaceuticals. Therefore, the correlation between renal uptake in PET/CT imaging and renal function should be investigated. (2) Methods: A group of 103 male patients were retrospectively evaluated for eGFR according to the CKD-EPI equation, tracer uptake intensity (SUVmax, SUVpeak, SUVmean), the molecular volume of the renal cortex, morphological kidney size, and total renal uptake. Manual and three different computer-assisted contouring methods (thresholds at 50% of SUVmax, 30% of SUVmax, and absolute SUV of 20) were used for measurements. Correlations between parameters were calculated using linear regression models. (3) Results: Renal SUVmax, SUVpeak, and SUVmean do not correlate with eGFR for manual or computer-assisted measurements. In contrast, molecular cortex volume shows a moderate correlation with eGFR (R2 = 0.231, p < 0.001), superior to morphological kidney size. A contouring threshold of 30% of SUVmax outperformed the other settings for renal cortex volume and total renal uptake. (4) Conclusions: Renal uptake of [68Ga]Ga-PSMA-11 cannot predict eGFR, but the functional renal cortex can be quantified by PET/CT imaging.
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Affiliation(s)
| | | | | | | | - Martin Freesmeyer
- Clinic of Nuclear Medicine, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
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de Roode KE, Joosten L, Behe M. Towards the Magic Radioactive Bullet: Improving Targeted Radionuclide Therapy by Reducing the Renal Retention of Radioligands. Pharmaceuticals (Basel) 2024; 17:256. [PMID: 38399470 PMCID: PMC10892921 DOI: 10.3390/ph17020256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 02/07/2024] [Accepted: 02/09/2024] [Indexed: 02/25/2024] Open
Abstract
Targeted radionuclide therapy (TRT) is an emerging field and has the potential to become a major pillar in effective cancer treatment. Several pharmaceuticals are already in routine use for treating cancer, and there is still a high potential for new compounds for this application. But, a major issue for many radiolabeled low-to-moderate-molecular-weight molecules is their clearance via the kidneys and their subsequent reuptake. High renal accumulation of radioactive compounds may lead to nephrotoxicity, and therefore, the kidneys are often the dose-limiting organs in TRT with these radioligands. Over the years, different strategies have been developed aiming for reduced kidney retention and enhanced therapeutic efficacy of radioligands. In this review, we will give an overview of the efforts and achievements of the used strategies, with focus on the therapeutic potential of low-to-moderate-molecular-weight molecules. Among the strategies discussed here is coadministration of compounds that compete for binding to the endocytic receptors in the proximal tubuli. In addition, the influence of altering the molecular design of radiolabeled ligands on pharmacokinetics is discussed, which includes changes in their physicochemical properties and implementation of cleavable linkers or albumin-binding moieties. Furthermore, we discuss the influence of chelator and radionuclide choice on reabsorption of radioligands by the kidneys.
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Affiliation(s)
- Kim E. de Roode
- Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands;
- Tagworks Pharmaceuticals, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands
| | - Lieke Joosten
- Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands;
| | - Martin Behe
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institut, 5232 Villigen, Switzerland
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Verena A, Merkens H, Chen CC, Chapple DE, Wang L, Bendre S, Wong AAWL, Bénard F, Lin KS. Synthesis and Preclinical Evaluation of Two Novel 68Ga-Labeled Bispecific PSMA/FAP-Targeted Tracers with 2-Nal-Containing PSMA-Targeted Pharmacophore and Pyridine-Based FAP-Targeted Pharmacophore. Molecules 2024; 29:800. [PMID: 38398552 PMCID: PMC10892057 DOI: 10.3390/molecules29040800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/06/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024] Open
Abstract
Some bispecific radiotracers have been developed to overcome the limitations of monospecific tracers and improve detection sensitivity for heterogeneous tumor lesions. Here, we aim to synthesize two bispecific tracers targeting prostate-specific membrane antigen (PSMA) and fibroblast activation protein (FAP), which are key markers expressed in prostate cancer. A pyridine-based FAP-targeted ligand was synthesized through multi-step organic synthesis and then connected to the 2-Nal-containing PSMA-targeted motif. The Ki(PSMA) values of Ga-complexed bispecific ligands, Ga-AV01084 and Ga-AV01088, were 11.6 ± 3.25 and 28.7 ± 6.05 nM, respectively, and the IC50(FAP) values of Ga-AV01084 and Ga-AV01088 were 10.9 ± 0.67 and 16.7 ± 1.53 nM, respectively. Both [68Ga]Ga-AV01084 and [68Ga]Ga-AV01088 enabled the visualization of PSMA-expressing LNCaP tumor xenografts and FAP-expressing HEK293T:hFAP tumor xenografts in PET images acquired at 1 h post-injection. However, the tumor uptake values from the bispecific tracers were still lower than those obtained from the monospecific tracers, PSMA-targeted [68Ga]Ga-PSMA-617 and FAP-targeted [68Ga]Ga-AV02070. Further investigations are needed to optimize the selection of linkers and targeted pharmacophores to improve the tumor uptake of bispecific PSMA/FAP tracers for prostate cancer imaging.
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Affiliation(s)
- Arsyangela Verena
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
| | - Chao-Cheng Chen
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
| | - Devon E. Chapple
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
| | - Lei Wang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
| | - Shreya Bendre
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
| | - Antonio A. W. L. Wong
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
| | - François Bénard
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC V5Z4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z1M9, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada; (A.V.); (H.M.); (C.-C.C.); (D.E.C.); (L.W.); (S.B.); (A.A.W.L.W.); (F.B.)
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC V5Z4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z1M9, Canada
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Randhawa P, Carbo-Bague I, Davey PRWJ, Chen S, Merkens H, Uribe CF, Zhang C, Tosato M, Bénard F, Radchenko V, Ramogida CF. Exploration of commercial cyclen-based chelators for mercury-197 m/g incorporation into theranostic radiopharmaceuticals. Front Chem 2024; 12:1292566. [PMID: 38389726 PMCID: PMC10881723 DOI: 10.3389/fchem.2024.1292566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 01/23/2024] [Indexed: 02/24/2024] Open
Abstract
A comprehensive investigation of the Hg2+ coordination chemistry and 197m/gHg radiolabeling capabilities of cyclen-based commercial chelators, namely, DOTA and DOTAM (aka TCMC), along with their bifunctional counterparts, p-SCN-Bn-DOTA and p-SCN-Bn-TCMC, was conducted to assess the suitability of these frameworks as bifunctional chelators for the 197m/gHg2+ theranostic pair. Radiolabeling studies revealed that TCMC and DOTA exhibited low radiochemical yields (0%-6%), even when subjected to harsh conditions (80°C) and high ligand concentrations (10-4 M). In contrast, p-SCN-Bn-TCMC and p-SCN-Bn-DOTA demonstrated significantly higher 197m/gHg radiochemical yields (100% ± 0.0% and 70.9% ± 1.1%, respectively) under the same conditions. The [197 m/gHg]Hg-p-SCN-Bn-TCMC complex was kinetically inert when challenged against human serum and glutathione. To understand the differences in labeling between the commercial chelators and their bifunctional counterparts, non-radioactive natHg2+ complexes were assessed using NMR spectroscopy and DFT calculations. The NMR spectra of Hg-TCMC and Hg-p-SCN-Bn-TCMC suggested binding of the Hg2+ ion through the cyclen backbone framework. DFT studies indicated that binding of the Hg2+ ion within the backbone forms a thermodynamically stable product. However, competition can form between isothiocyanate binding and binding through the macrocycle, which was experimentally observed. The isothiocyanate bound coordination product was dominant at the radiochemical scale as, in comparison, the macrocycle bound product was seen at the NMR scale, agreeing with the DFT result. Furthermore, a bioconjugate of TCMC (TCMC-PSMA) targeting prostate-specific membrane antigen was synthesized and radiolabeled, resulting in an apparent molar activity of 0.089 MBq/nmol. However, the complex demonstrated significant degradation over 24 h when exposed to human serum and glutathione. Subsequently, cell binding assays were conducted, revealing a Ki value ranging from 19.0 to 19.6 nM. This research provides crucial insight into the effectiveness of current commercial chelators in the context of 197m/gHg2+ radiolabeling. It underscores the necessity for the development of specific and customized chelators to these unique "soft" radiometals to advance 197m/gHg2+ radiopharmaceuticals.
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Affiliation(s)
- Parmissa Randhawa
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
- Life Sciences Division, TRIUMF, Vancouver, BC, Canada
| | - Imma Carbo-Bague
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
- Life Sciences Division, TRIUMF, Vancouver, BC, Canada
| | - Patrick R W J Davey
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
- Life Sciences Division, TRIUMF, Vancouver, BC, Canada
| | - Shaohuang Chen
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
- Life Sciences Division, TRIUMF, Vancouver, BC, Canada
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer, Vancouver, BC, Canada
| | - Carlos F Uribe
- Department of Molecular Oncology, BC Cancer, Vancouver, BC, Canada
| | - Chengcheng Zhang
- Department of Molecular Oncology, BC Cancer, Vancouver, BC, Canada
| | - Marianna Tosato
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
- Life Sciences Division, TRIUMF, Vancouver, BC, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer, Vancouver, BC, Canada
| | - Valery Radchenko
- Life Sciences Division, TRIUMF, Vancouver, BC, Canada
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
| | - Caterina F Ramogida
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
- Life Sciences Division, TRIUMF, Vancouver, BC, Canada
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8
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Wang L, Kuo HT, Zhang Z, Zhang C, Chen CC, Chapple D, Wilson R, Colpo N, François Bénard, Lin KS. Unnatural amino acid substitutions to improve in vivo stability and tumor uptake of 68Ga-labeled GRPR-targeted TacBOMB2 derivatives for cancer imaging with positron emission tomography. EJNMMI Radiopharm Chem 2024; 9:8. [PMID: 38305955 PMCID: PMC10837402 DOI: 10.1186/s41181-024-00241-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/25/2024] [Indexed: 02/03/2024] Open
Abstract
BACKGROUND Overexpressed in various solid tumors, gastrin-releasing peptide receptor (GRPR) is a promising cancer imaging marker and therapeutic target. Although antagonists are preferable for the development of GRPR-targeted radiopharmaceuticals due to potentially fewer side effects, internalization of agonists may lead to longer tumor retention and better treatment efficacy. In this study, we systematically investigated unnatural amino acid substitutions to improve in vivo stability and tumor uptake of a previously reported GRPR-targeted agonist tracer, [68Ga]Ga-TacBOMB2 (68Ga-DOTA-Pip-D-Phe6-Gln7-Trp8-Ala9-Val10-Gly11-His12-Leu13-Thz14-NH2). RESULTS Unnatural amino acid substitutions were conducted for Gln7, Trp8, Ala9, Val10, Gly11 and His12, either alone or in combination. Out of 25 unnatural amino acid substitutions, tert-Leu10 (Tle10) and NMe-His12 substitutions were identified to be preferable modifications especially in combination. Compared with the previously reported [68Ga]Ga-TacBOMB2, the Tle10 and NMe-His12 derived [68Ga]Ga-LW01110 showed retained agonist characteristics and improved GRPR binding affinity (Ki = 7.62 vs 1.39 nM), in vivo stability (12.7 vs 89.0% intact tracer in mouse plasma at 15 min post-injection) and tumor uptake (5.95 vs 16.6 %ID/g at 1 h post-injection). CONCLUSIONS Unnatural amino acid substitution is an effective strategy to improve in vivo stability and tumor uptake of peptide-based radiopharmaceuticals. With excellent tumor uptake and tumor-to-background contrast, [68Ga]Ga-LW01110 is promising for detecting GRPR-expressing cancer lesions with PET. Since agonists can lead to internalization upon binding to receptors and foreseeable long tumor retention, our optimized GRPR-targeted sequence, [Tle10,NMe-His12,Thz14]Bombesin(7-14), is a promising template for use for the design of GRPR-targeted radiotherapeutic agents.
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Affiliation(s)
- Lei Wang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
| | - Chengcheng Zhang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
| | - Chao-Cheng Chen
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
| | - Devon Chapple
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
| | - Ryan Wilson
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
| | - Nadine Colpo
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC, V5Z4E6, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC, V5Z4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC, V5Z1M9, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, V5Z1L3, Canada.
- Department of Molecular Imaging and Therapy, BC Cancer, Vancouver, BC, V5Z4E6, Canada.
- Department of Radiology, University of British Columbia, Vancouver, BC, V5Z1M9, Canada.
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9
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Bolzati C, Gobbi C, Ferro-Flores G, Turato S, Ocampo-Garcia B, Carpanese D, Marzano C, Spolaore B, Fracasso G, Rosato A, Meléndez-Alafort L. Development and Characterization of 99mTc-scFvD2B as a Potential Radiopharmaceutical for SPECT Imaging of Prostate Cancer. Int J Mol Sci 2023; 25:492. [PMID: 38203663 PMCID: PMC10779128 DOI: 10.3390/ijms25010492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/22/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024] Open
Abstract
Previously, we demonstrated that the 177Lu-labeled single-chain variable fragment of an anti-prostate-specific membrane antigen (PSMA) IgG D2B antibody (scFvD2B) showed higher prostate cancer (PCa) cell uptake and tumor radiation doses compared to 177Lu-labeled Glu-ureide-based PSMA inhibitory peptides. To obtain a 99mTc-/177Lu-scFvD2B theranostic pair, this research aimed to synthesize and biochemically characterize a novel 99mTc-scFvD2B radiotracer. The scFvD2B-Tag and scFvD2B antibody fragments were produced and purified. Then, two HYNIC derivatives, HYNIC-Gly-Gly-Cys-NH2 (HYNIC-GGC) and succinimidyl-HYNIC (S-HYNIC), were used to conjugate the scFvD2B-Tag and scFvD2B isoforms, respectively. Subsequently, chemical characterization, immunoreactivity tests (affinity and specificity), radiochemical purity tests, stability tests in human serum, cellular uptake and internalization in LNCaP(+), PC3-PIP(++) or PC3(-) PCa cells of the resulting unlabeled HYNIC-scFvD2B conjugates (HscFv) and 99mTc-HscFv agents were performed. The results showed that incorporating HYNIC as a chelator did not affect the affinity, specificity or stability of scFvD2B. After purification, the radiochemical purity of 99mTc-HscFv radiotracers was greater than 95%. A two-sample t-test of 99mTc-HscFv1 and 99mTc-HscFv1 uptake in PC3-PIP vs. PC3 showed a p-value < 0.001, indicating that the PSMA receptor interaction of 99mTc-HscFv agents was statistically significantly higher in PSMA-positive cells than in the negative controls. In conclusion, the results of this research warrant further preclinical studies to determine whether the in vivo pharmacokinetics and tumor uptake of 99mTc-HscFv still offer sufficient advantages over HYNIC-conjugated peptides to be considered for SPECT/PSMA imaging.
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Affiliation(s)
- Cristina Bolzati
- Institute of Condensed Matter Chemistry and Energy Technologies, Consiglio Nazionale delle Ricerche, Corso Stati Uniti 4, 35127 Padova, Italy; (C.B.); (C.G.)
| | - Carolina Gobbi
- Institute of Condensed Matter Chemistry and Energy Technologies, Consiglio Nazionale delle Ricerche, Corso Stati Uniti 4, 35127 Padova, Italy; (C.B.); (C.G.)
| | - Guillermina Ferro-Flores
- Laboratorio Nacional de Investigación y Desarrollo de Radiofármacos, Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N. La Marquesa, Ocoyoacac 52750, Mexico; (G.F.-F.); (B.O.-G.)
| | - Sofia Turato
- Istituto Oncologico Veneto IOV-IRCCS, Via Gattamelata 64, 35138 Padova, Italy; (S.T.); (A.R.)
| | - Blanca Ocampo-Garcia
- Laboratorio Nacional de Investigación y Desarrollo de Radiofármacos, Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N. La Marquesa, Ocoyoacac 52750, Mexico; (G.F.-F.); (B.O.-G.)
| | - Debora Carpanese
- Istituto Oncologico Veneto IOV-IRCCS, Via Gattamelata 64, 35138 Padova, Italy; (S.T.); (A.R.)
| | - Cristina Marzano
- Dipartimento di Scienze del Farmaco, Università degli Studi di Padova, Via Marzolo 5, 35131 Padova, Italy; (C.M.); (B.S.)
| | - Barbara Spolaore
- Dipartimento di Scienze del Farmaco, Università degli Studi di Padova, Via Marzolo 5, 35131 Padova, Italy; (C.M.); (B.S.)
| | - Giulio Fracasso
- Dipartimento di Scienze Biomediche, Università degli Studi di Padova, Viale G. Colombo 3, 35131 Padova, Italy
| | - Antonio Rosato
- Istituto Oncologico Veneto IOV-IRCCS, Via Gattamelata 64, 35138 Padova, Italy; (S.T.); (A.R.)
- Dipartimento di Scienze Chirurgiche Oncologiche e Gastroenterologiche, Università degli Studi di Padova, Via Gattamelata 64, 35138 Padova, Italy
| | - Laura Meléndez-Alafort
- Istituto Oncologico Veneto IOV-IRCCS, Via Gattamelata 64, 35138 Padova, Italy; (S.T.); (A.R.)
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10
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Bezverkhniaia E, Kanellopoulos P, Abouzayed A, Larkina M, Oroujeni M, Vorobyeva A, Rosenström U, Tolmachev V, Orlova A. Preclinical Evaluation of a Novel High-Affinity Radioligand [ 99mTc]Tc-BQ0413 Targeting Prostate-Specific Membrane Antigen (PSMA). Int J Mol Sci 2023; 24:17391. [PMID: 38139219 PMCID: PMC10743726 DOI: 10.3390/ijms242417391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/02/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
Radionuclide imaging using radiolabeled inhibitors of prostate-specific membrane antigen (PSMA) can be used for the staging of prostate cancer. Previously, we optimized the Glu-urea-Lys binding moiety using a linker structure containing 2-napththyl-L-alanine and L-tyrosine. We have now designed a molecule that contains mercaptoacetyl-triglutamate chelator for labeling with Tc-99m (designated as BQ0413). The purpose of this study was to evaluate the imaging properties of [99mTc]Tc-BQ0413. PSMA-transfected PC3-pip cells were used to evaluate the specificity and affinity of [99mTc]Tc-BQ0413 binding in vitro. PC3-pip tumor-bearing BALB/C nu/nu mice were used as an in vivo model. [99mTc]Tc-BQ0413 bound specifically to PC3-pip cells with an affinity of 33 ± 15 pM. In tumor-bearing mice, the tumor uptake of [99mTc]Tc-BQ0413 (38 ± 6 %IA/g in PC3-pip 3 h after the injection of 40 pmol) was dependent on PSMA expression (3 ± 2 %IA/g and 0.9 ± 0.3 %IA/g in PSMA-negative PC-3 and SKOV-3 tumors, respectively). We show that both unlabeled BQ0413 and the commonly used binder PSMA-11 enable the blocking of [99mTc]Tc-BQ0413 uptake in normal PSMA-expressing tissues without blocking the uptake in tumors. This resulted in an appreciable increase in tumor-to-organ ratios. At the same injected mass (5 nmol), the use of BQ0413 was more efficient in suppressing renal uptake than the use of PSMA-11. In conclusion, [99mTc]Tc-BQ0413 is a promising probe for the visualization of PSMA-positive lesions using single-photon emission computed tomography (SPECT).
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Affiliation(s)
- Ekaterina Bezverkhniaia
- Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden; (E.B.); (P.K.); (A.A.); (U.R.)
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634009 Tomsk, Russia;
- Scientific and Research Laboratory of Chemical and Pharmaceutical Research, Siberian State Medical University, 634050 Tomsk, Russia
| | - Panagiotis Kanellopoulos
- Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden; (E.B.); (P.K.); (A.A.); (U.R.)
| | - Ayman Abouzayed
- Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden; (E.B.); (P.K.); (A.A.); (U.R.)
| | - Mariia Larkina
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634009 Tomsk, Russia;
- Scientific and Research Laboratory of Chemical and Pharmaceutical Research, Siberian State Medical University, 634050 Tomsk, Russia
| | - Maryam Oroujeni
- Department of Immunology, Genetics and Pathology, Uppsala University, 752 37 Uppsala, Sweden; (M.O.); (A.V.); (V.T.)
- Affibody AB, 171 65 Solna, Sweden
| | - Anzhelika Vorobyeva
- Department of Immunology, Genetics and Pathology, Uppsala University, 752 37 Uppsala, Sweden; (M.O.); (A.V.); (V.T.)
| | - Ulrika Rosenström
- Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden; (E.B.); (P.K.); (A.A.); (U.R.)
| | - Vladimir Tolmachev
- Department of Immunology, Genetics and Pathology, Uppsala University, 752 37 Uppsala, Sweden; (M.O.); (A.V.); (V.T.)
| | - Anna Orlova
- Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden; (E.B.); (P.K.); (A.A.); (U.R.)
- Science for Life Laboratory, Uppsala University, 752 37 Uppsala, Sweden
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11
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Hasnowo LA, Larkina MS, Plotnikov E, Bodenko V, Yuldasheva F, Stasyuk E, Petrov SA, Zyk NY, Machulkin AE, Vorozhtsov NI, Beloglazkina EK, Nenajdenko VG, Tolmachev V, Orlova A, Majouga AG, Yusubov MS. Synthesis, 123I-Radiolabeling Optimization, and Initial Preclinical Evaluation of Novel Urea-Based PSMA Inhibitors with a Tributylstannyl Prosthetic Group in Their Structures. Int J Mol Sci 2023; 24:12206. [PMID: 37569582 PMCID: PMC10418939 DOI: 10.3390/ijms241512206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/24/2023] [Accepted: 07/24/2023] [Indexed: 08/13/2023] Open
Abstract
Prostate-specific membrane antigen (PSMA) has been identified as a target for the development of theranostic agents. In our current work, we describe the design and synthesis of novel N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-(S)-L-lysine (DCL) urea-based PSMA inhibitors with a chlorine-substituted aromatic fragment at the lysine ε-nitrogen atom, a dipeptide including two phenylalanine residues in the L-configuration as the peptide fragment of the linker, and 3- or 4-(tributylstannyl)benzoic acid as a prosthetic group in their structures for radiolabeling. The standard compounds [127I]PSMA-m-IB and [127I]PSMA-p-IB for comparative and characterization studies were first synthesized using two alternative synthetic approaches. An important advantage of the alternative synthetic approach, in which the prosthetic group (NHS-activated esters of compounds) is first conjugated with the polypeptide sequence followed by replacement of the Sn(Bu)3 group with radioiodine, is that the radionuclide is introduced in the final step of synthesis, thereby minimizing operating time with iodine-123 during the radiolabeling process. The obtained DCL urea-based PSMA inhibitors were radiolabeled with iodine-123. The radiolabeling optimization results showed that the radiochemical yield of [123I]PSMA-p-IB was higher than that of [123I]PSMA-m-IB, which were 74.9 ± 1.0% and 49.4 ± 1.2%, respectively. The radiochemical purity of [123I]PSMA-p-IB after purification was greater than 99.50%. The initial preclinical evaluation of [123I]PSMA-p-IB demonstrated a considerable affinity and specific binding to PC-3 PIP (PSMA-expressing cells) in vitro. The in vivo biodistribution of this new radioligand [123I]PSMA-p-IB showed less accumulation than [177Lu]Lu-PSMA-617 in several normal organs (liver, kidney, and bone). These results warrant further preclinical development, including toxicology evaluation and experiments in tumor-bearing mice.
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Affiliation(s)
- Lutfi A. Hasnowo
- School of Nuclear Science and Engineering, Tomsk Polytechnic University, Tomsk 634050, Russia or (L.A.H.); (E.S.)
- Polytechnic Institute of Nuclear Technology, National Research and Innovation Agency, Yogyakarta 55281, Indonesia
| | - Maria S. Larkina
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Tomsk 634050, Russia; (M.S.L.); (E.P.); (V.B.); (F.Y.); (M.S.Y.)
- Department of Pharmaceutical Analysis, Siberian State Medical University, Tomsk 634050, Russia
| | - Evgenii Plotnikov
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Tomsk 634050, Russia; (M.S.L.); (E.P.); (V.B.); (F.Y.); (M.S.Y.)
- Mental Health Reseach Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Tomsk 634014, Russia
| | - Vitalina Bodenko
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Tomsk 634050, Russia; (M.S.L.); (E.P.); (V.B.); (F.Y.); (M.S.Y.)
- Department of Pharmaceutical Analysis, Siberian State Medical University, Tomsk 634050, Russia
| | - Feruza Yuldasheva
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Tomsk 634050, Russia; (M.S.L.); (E.P.); (V.B.); (F.Y.); (M.S.Y.)
| | - Elena Stasyuk
- School of Nuclear Science and Engineering, Tomsk Polytechnic University, Tomsk 634050, Russia or (L.A.H.); (E.S.)
| | - Stanislav A. Petrov
- Department of Chemistry, M.V. Lomonosov Moscow State University Leninskie Gory, 1–3, Moscow 119991, Russia; (S.A.P.); (N.Y.Z.); (A.E.M.); (N.I.V.); (V.G.N.)
| | - Nikolai Y. Zyk
- Department of Chemistry, M.V. Lomonosov Moscow State University Leninskie Gory, 1–3, Moscow 119991, Russia; (S.A.P.); (N.Y.Z.); (A.E.M.); (N.I.V.); (V.G.N.)
| | - Aleksei E. Machulkin
- Department of Chemistry, M.V. Lomonosov Moscow State University Leninskie Gory, 1–3, Moscow 119991, Russia; (S.A.P.); (N.Y.Z.); (A.E.M.); (N.I.V.); (V.G.N.)
| | - Nikolai I. Vorozhtsov
- Department of Chemistry, M.V. Lomonosov Moscow State University Leninskie Gory, 1–3, Moscow 119991, Russia; (S.A.P.); (N.Y.Z.); (A.E.M.); (N.I.V.); (V.G.N.)
| | - Elena K. Beloglazkina
- Department of Chemistry, M.V. Lomonosov Moscow State University Leninskie Gory, 1–3, Moscow 119991, Russia; (S.A.P.); (N.Y.Z.); (A.E.M.); (N.I.V.); (V.G.N.)
| | - Valentine G. Nenajdenko
- Department of Chemistry, M.V. Lomonosov Moscow State University Leninskie Gory, 1–3, Moscow 119991, Russia; (S.A.P.); (N.Y.Z.); (A.E.M.); (N.I.V.); (V.G.N.)
| | - Vladimir Tolmachev
- Department of Immunology, Genetics and Pathology, Uppsala University, 75185 Uppsala, Sweden;
| | - Anna Orlova
- Department of Medicinal Chemistry, Uppsala University, 75183 Uppsala, Sweden;
| | - Alexander G. Majouga
- Faculty of Chemistry, Dmitry Mendeleev University of Chemical Technology of Russia, Miusskaya sq. 9, Moscow 125047, Russia;
| | - Mekhman S. Yusubov
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Tomsk 634050, Russia; (M.S.L.); (E.P.); (V.B.); (F.Y.); (M.S.Y.)
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12
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Lu K, Zhang C, Zhang Z, Kuo HT, Colpo N, Bénard F, Lin KS. Synthesis and Evaluation of 99mTc-Labeled PSMA-Targeted Tracers Based on the Lys-Urea-Aad Pharmacophore for Detecting Prostate Cancer with Single Photon Emission Computed Tomography. Molecules 2023; 28:5120. [PMID: 37446782 DOI: 10.3390/molecules28135120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 06/23/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
Prostate-specific membrane antigen (PSMA) is a well-validated prostate cancer marker but reported PSMA-targeted tracers derived from the Lys-urea-Glu pharmacophore including the clinically validated [99mTc]Tc-EDDA/HYNIC-iPSMA have high off-target uptake in kidneys, spleen, and salivary glands. In this study, we synthesized and evaluated three novel 99mTc-labeled PSMA-targeted tracers and investigated if the tracers derived from the Lys-urea-Aad pharmacophore could have minimized uptake in off-target organs/tissues. In vitro competition binding assays showed that compared with HYNIC-iPSMA, the three novel ligands had slightly weaker PSMA binding affinity (average Ki = 3.11 vs. 8.96-11.6 nM). Imaging and ex vivo biodistribution studies in LNCaP tumor-bearing mice showed that [99mTc]Tc-EDDA/HYNIC-iPSMA and the three novel tracers successfully visualized LNCaP tumor xenografts in SPECT images and were excreted mainly via the renal pathway. The average tumor uptake at 1 h post-injection varied from 5.40 to 18.8%ID/g, and the tracers derived from the Lys-urea-Aad pharmacophore had much lower uptake in the spleen and salivary glands. Compared with the clinical tracer [99mTc]Tc-EDDA/HYNIC-iPSMA, the Lys-urea-Aad-derived [99mTc]Tc-EDDA-KL01127 had lower background uptake and superior tumor-to-background contrast ratios and is therefore promising for clinical translation to detect prostate cancer lesions with SPECT.
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Affiliation(s)
- Kelly Lu
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada
| | - Chengcheng Zhang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada
| | - Nadine Colpo
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada
- Department of Functional Imaging, BC Cancer Research Institute, Vancouver, BC V5Z 4E6, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada
- Department of Functional Imaging, BC Cancer Research Institute, Vancouver, BC V5Z 4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z 1L3, Canada
- Department of Functional Imaging, BC Cancer Research Institute, Vancouver, BC V5Z 4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
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13
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68Ga-Labeled [Thz 14]Bombesin(7-14) Analogs: Promising GRPR-Targeting Agonist PET Tracers with Low Pancreas Uptake. Molecules 2023; 28:molecules28041977. [PMID: 36838968 PMCID: PMC9962964 DOI: 10.3390/molecules28041977] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 02/15/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
With overexpression in various cancers, the gastrin-releasing peptide receptor (GRPR) is a promising target for cancer imaging and therapy. However, the high pancreas uptake of reported GRPR-targeting radioligands limits their clinical application. Our goal was to develop 68Ga-labeled agonist tracers for detecting GRPR-expressing tumors with positron emission tomography (PET), and compare them with the clinically validated agonist PET tracer, [68Ga]Ga-AMBA. Ga-TacBOMB2, TacBOMB3, and TacBOMB4, derived from [Thz14]Bombesin(7-14), were confirmed to be GRPR agonists by a calcium mobilization study, and their binding affinities (Ki(GRPR)) were determined to be 7.62 ± 0.19, 6.02 ± 0.59, and 590 ± 36.5 nM, respectively, via in vitro competition binding assays. [68Ga]Ga-TacBOMB2, [68Ga]Ga-TacBOMB3, and [68Ga]Ga-AMBA clearly visualized PC-3 tumor xenografts in a PET imaging study. [68Ga]Ga-TacBOMB2 showed comparable tumor uptake but superior tumor-to-background contrast ratios when compared to [68Ga]Ga-AMBA. Moreover, [68Ga]Ga-TacBOMB2 and [68Ga]Ga-TacBOMB3 showed a much lower rate of uptake in the pancreas (1.30 ± 0.14 and 2.41 ± 0.72%ID/g, respectively) than [68Ga]Ga-AMBA (62.4 ± 4.26%ID/g). In conclusion, replacing Met14 in the GRPR-targeting sequence with Thz14 retains high GRPR-binding affinity and agonist properties. With good tumor uptake and tumor-to-background uptake ratios, [68Ga]Ga-TacBOMB2 is promising for detecting GRPR-expressing tumors. The much lower pancreas uptake of [68Ga]Ga-TacBOMB2 and [68Ga]Ga-TacBOMB3 suggests that [Thz14]Bombesin(7-14) is a promising targeting vector for the design of GRPR-targeting radiopharmaceuticals, especially for radioligand therapy application.
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14
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Cai P, Tang S, Xia L, Wang Y, Liu Y, Feng Y, Liu N, Chen Y, Zhou Z. Improve the Biodistribution with Bulky and Lipophilic Modification Strategies on Lys-Urea-Glu-Based PSMA-Targeting Radiotracers. Mol Pharm 2023; 20:1435-1446. [PMID: 36696174 DOI: 10.1021/acs.molpharmaceut.2c01101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Since prostate-specific membrane antigen (PSMA) is upregulated in nearly all stages of prostate cancer (PCa), PSMA can be considered a viable diagnostic biomarker and treatment target in PCa. In this study, we have developed five 68Ga-labeled PSMA-targeted tracers, 68Ga-Flu-1, 68Ga-Flu-2, 68Ga-9-Ant, 68Ga-1-Nal, and 68Ga-1-Noi, to investigate the effect of lipophilic bulky groups on the pharmacokinetics of PSMA inhibitors compared to 68Ga-PSMA-11 and then explore their in vitro and in vivo properties. 68Ga-labeled PSMA inhibitors were obtained in 88.53-99.98% radiochemical purity and at the highest specific activity of up to 20 MBq/μg. These compounds revealed a highly efficient uptake and internalization into LNCaP cells and increased over time. PET imaging and biodistribution studies were performed in mice bearing PSMA expressing LNCaP prostate cancer xenografts. All tracers enabled clear visualization of tumors in PET images with excellent tumor-to-background contrast. The biodistribution studies showed that all these radioligands were excreted mainly via the renal pathway. The in vivo biodistribution of 68Ga-Flu-1 revealed higher tumor uptake (40.11 ± 9.24 %ID/g at 2 h p.i.) compared to 68Ga-PSMA-11 (28.10 ± 5.96 %ID/g at 2 h p.i.). Both in vitro and in vivo experiments showed that chemical modification of the lysine fragment significantly impacts tumor-targeting and pharmacokinetic properties. Great potential to serve as new PET tracers for prostate cancer has been revealed with these radiotracers─68Ga-Flu-1 in particular.
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Affiliation(s)
- Ping Cai
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
| | - Sufan Tang
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
| | - Li Xia
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
| | - Yinwen Wang
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
| | - Yang Liu
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
| | - Yue Feng
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
| | - Nan Liu
- Department of Nuclear Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Yue Chen
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
| | - Zhijun Zhou
- Department of Nuclear Medicine, Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Jiangyang District, Luzhou 646000, Sichuan, China.,Institute of Nuclear Medicine, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China.,Department of Pharmaceutics, School of Pharmacy, Southwest Medical University, Jiangyang District, Luzhou 646000, Sichuan, China
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15
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Verena A, Zhang Z, Kuo HT, Merkens H, Zeisler J, Wilson R, Bendre S, Wong AAWL, Bénard F, Lin KS. Synthesis and Preclinical Evaluation of Three Novel 68Ga-Labeled Bispecific PSMA/FAP-Targeting Tracers for Prostate Cancer Imaging. Molecules 2023; 28:molecules28031088. [PMID: 36770755 PMCID: PMC9921851 DOI: 10.3390/molecules28031088] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 01/15/2023] [Accepted: 01/19/2023] [Indexed: 01/24/2023] Open
Abstract
Tumor heterogeneity limits the efficacy and reliability of monospecific radiopharmaceuticals in prostate cancer diagnosis and therapy. To overcome this limitation and improve lesion detection sensitivity, we developed and evaluated three bispecific radiotracers that can target both prostate-specific membrane antigen (PSMA) and fibroblast activation protein (FAP), which are the two key proteins overexpressed in prostate cancer. Three FAP-targeting ligands with various linker lengths were synthesized through multistep organic synthesis, and then connected to the PSMA-targeting motif. IC50(PSMA) and IC50(FAP) values of Ga-complexed bispecific ligands, Ga-AV01017, Ga-AV01030, and Ga-AV01038 were 25.2-71.6 and 1.25-2.74 nM, respectively. The uptake values in PSMA-expressing LNCaP tumor xenografts were 4.38 ± 0.55, 5.17 ± 0.51, and 4.25 ± 0.86 %ID/g for [68Ga]Ga-AV01017, [68Ga]Ga-AV01030, and [68Ga]Ga-AV01038, respectively, which were lower than the monospecific PSMA-targeting tracer [68Ga]Ga-HTK03041 (23.1 ± 6.11 %ID/g). The uptake values in FAP-expressing HEK293T:hFAP tumor xenografts were 2.99 ± 0.37, 3.69 ± 0.81, 3.64 ± 0.83 %ID/g for [68Ga]Ga-AV01017, [68Ga]Ga-AV01030, and [68Ga]Ga-AV01038, respectively, which were also lower than the monospecific FAP-targeting tracer, [68Ga]Ga-FAPI-04 (12.5 ± 2.00 %ID/g). We observed that the bispecific tracers had prolonged blood retention, in which tracers with a longer linker tend to have a higher blood uptake and lower tumor uptake. Further investigations are needed to optimize the linker selection to generate promising bispecific PSMA/FAP-targeting tracers for prostate cancer imaging.
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Affiliation(s)
- Arsyangela Verena
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - Jutta Zeisler
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - Ryan Wilson
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - Shreya Bendre
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - Antonio A. W. L. Wong
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z1M9, Canada
- Department of Functional Imaging, BC Cancer, Vancouver, BC V5Z4E6, Canada
- Correspondence: (F.B.); (K.-S.L.); Tel.: +1-604-675-8208 (K.-S.L.)
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC V5Z1L3, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z1M9, Canada
- Department of Functional Imaging, BC Cancer, Vancouver, BC V5Z4E6, Canada
- Correspondence: (F.B.); (K.-S.L.); Tel.: +1-604-675-8208 (K.-S.L.)
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16
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Brandt F, Ullrich M, Wodtke J, Kopka K, Bachmann M, Löser R, Pietzsch J, Pietzsch HJ, Wodtke R. Enzymological Characterization of 64Cu-Labeled Neprilysin Substrates and Their Application for Modulating the Renal Clearance of Targeted Radiopharmaceuticals. J Med Chem 2023; 66:516-537. [PMID: 36595224 DOI: 10.1021/acs.jmedchem.2c01472] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The applicability of radioligands for targeted endoradionuclide therapy is limited due to radiation-induced toxicity to healthy tissues, in particular to the kidneys as primary organs of elimination. The targeting of enzymes of the renal brush border membrane by cleavable linkers that permit the formation of fast eliminating radionuclide-carrying cleavage fragments gains increasing interest. Herein, we synthesized a small library of 64Cu-labeled cleavable linkers and quantified their substrate potentials toward neprilysin (NEP), a highly abundant peptidase at the renal brush border membrane. This allowed for the derivation of structure-activity relationships, and selected cleavable linkers were attached to the somatostatin receptor subtype 2 ligand [Tyr3]octreotate. Radiopharmacological characterization revealed that a substrate-based targeting of NEP in the kidneys with small peptides entails their premature cleavage in the blood circulation by soluble and endothelium-derived NEP. However, for a kidney-specific targeting of NEP, the additional targeting of albumin in the blood is highlighted.
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Affiliation(s)
- Florian Brandt
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Martin Ullrich
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany
| | - Johanna Wodtke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany
| | - Klaus Kopka
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany.,National Center for Tumor Diseases (NCT) Dresden, University Hospital Carl Gustav Carus, Fetscherstraße 74, 01307Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, Fetscherstraße 74, 01307Dresden, Germany
| | - Michael Bachmann
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,National Center for Tumor Diseases (NCT) Dresden, University Hospital Carl Gustav Carus, Fetscherstraße 74, 01307Dresden, Germany
| | - Reik Löser
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Jens Pietzsch
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Hans-Jürgen Pietzsch
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Robert Wodtke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany
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17
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Krishnan MA, Pandit A, Sharma R, Chelvam V. Imaging of prostate cancer: optimizing affinity to prostate specific membrane antigen by spacer modifications in a tumor spheroid model. J Biomol Struct Dyn 2022; 40:9909-9930. [PMID: 34180367 DOI: 10.1080/07391102.2021.1936642] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Early diagnosis of prostate cancer (PCa) is crucial for staging, treatment and management of patients. Prostate specific membrane antigen (PSMA), highly over-expressed on PCa cells, is an excellent target for selective imaging of PCa. In recent years, various scaffolds have been explored as potential carriers to target diagnostic and therapeutic agents to PSMA+ tumour cells. Numerous fluorescent or radioisotope probes linked via a peptide linker have been developed that selectively binds to PCa cells. However, there are very few reports that examine the effects of chemical modifications in the peptide linker of an imaging probe on its affinity to PSMA protein. This report systematically investigates the impact of hydrophobic aromatic moieties in the peptide linker on PSMA affinity and in vitro performance. For this, a series of fluorescent bioconjugates 12-17 with different aromatic spacers were designed, synthesized, and their interactions within the PSMA pocket were first analysed in silico. Cell uptake studies were then performed for 12-17 in PSMA+ cell lines and 3D tumour models in vitro. Binding affinity values of 12-17 were found to be in the range of 36 to 157.9 nM, and 12 with three aromatic groups in the spacer exhibit highest affinity (KD = 36 nM) compared to 17 which is devoid of aromatic groups. These studies suggest that aromatic groups in the spacer region can significantly affect deep tissue imaging of fluorescent bioconjugates. Bioconjugate 12 can be a promising diagnostic tool, and conjugation to near-infrared agents would further its applications in deep-tissue imaging and surgery. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Mena Asha Krishnan
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Amit Pandit
- Department of Chemistry, Indian Institute of Technology Indore, Indore, India
| | - Rajesh Sharma
- School of Pharmacy, Devi Ahilya University, Indore, India
| | - Venkatesh Chelvam
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India.,Department of Chemistry, Indian Institute of Technology Indore, Indore, India
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18
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Hirata S, Mishiro K, Higashi T, Fuchigami T, Munekane M, Arano Y, Kinuya S, Ogawa K. Synthesis and evaluation of a multifunctional probe with a high affinity for prostate-specific membrane antigen (PSMA) and bone. Nucl Med Biol 2022; 114-115:34-41. [PMID: 36088875 DOI: 10.1016/j.nucmedbio.2022.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 12/27/2022]
Abstract
Prostate cancer frequently metastasizes to the bone. Because patients with bone metastases suffer from skeletal-related events, the diagnosis and treatment of bone metastases in the early stage are important. In this study, to improve the sensitivity of detecting bone metastases in patients with prostate cancer, we designed, synthesized, and evaluated a multifunctional radiotracer, [67Ga]Ga-D11-PSMA-617 ([67Ga]3), with an undeca-aspartic acid as a bone-seeking moiety between [67Ga]Ga-DOTA and a prostate-specific membrane antigen (PSMA) ligand based on the lysine-urea-glutamate motif. [67Ga]3 showed a high affinity for hydroxyapatite and high uptake in PSMA-positive LNCaP cells. Moreover, in biodistribution experiments using tumor-bearing mice, [67Ga]3 exhibited high accumulation in the bone and PSMA-positive tumor although the accumulation of [67Ga]3 in the PSMA-positive tumor was lower than that of [67Ga]Ga-PSMA-617. This study provides valuable information for developing radiotheranostic probes combining multiple carriers with different mechanisms.
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Affiliation(s)
- Saki Hirata
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Kenji Mishiro
- Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan
| | - Takuma Higashi
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Takeshi Fuchigami
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Masayuki Munekane
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Yasushi Arano
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Seigo Kinuya
- Department of Nuclear Medicine, Kanazawa University Hospital, Kanazawa University, Kanazawa 920-8641, Japan
| | - Kazuma Ogawa
- Graduate School of Medical Sciences, Kanazawa University, Kanazawa 920-1192, Japan; Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan.
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19
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Lau J, Lee H, Rousseau J, Bénard F, Lin KS. Application of Cleavable Linkers to Improve Therapeutic Index of Radioligand Therapies. Molecules 2022; 27:molecules27154959. [PMID: 35956909 PMCID: PMC9370263 DOI: 10.3390/molecules27154959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 01/11/2023] Open
Abstract
Radioligand therapy (RLT) is an emergent drug class for cancer treatment. The dose administered to cancer patients is constrained by the radiation exposure to normal tissues to maintain an appropriate therapeutic index. When a radiopharmaceutical or its radiometabolite is retained in the kidneys, radiation dose deposition in the kidneys can become a dose-limiting factor. A good exemplar is [177Lu]Lu-DOTATATE, where patients receive a co-infusion of basic amino acids for nephroprotection. Besides peptides, there are other classes of targeting vectors like antibody fragments, antibody mimetics, peptidomimetics, and small molecules that clear through the renal pathway. In this review, we will review established and emerging strategies that can be used to mitigate radiation-induced nephrotoxicity, with a focus on the development and incorporation of cleavable linkers for radiopharmaceutical designs. Finally, we offer our perspectives on cleavable linkers for RLT, highlighting future areas of research that will help advance the technology.
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Affiliation(s)
- Joseph Lau
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada
| | - Hwan Lee
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Julie Rousseau
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Correspondence: ; Tel.: +1-604-675-8208
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20
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Kwon D, Zhang Z, Zeisler J, Kuo HT, Lin KS, Benard F. Reducing the Kidney Uptake of High Contrast CXCR4 PET Imaging Agents via Linker Modifications. Pharmaceutics 2022; 14:pharmaceutics14071502. [PMID: 35890397 PMCID: PMC9316317 DOI: 10.3390/pharmaceutics14071502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/02/2022] [Accepted: 07/07/2022] [Indexed: 01/27/2023] Open
Abstract
Purpose: The C-X-C chemokine receptor 4 (CXCR4) is highly expressed in many subtypes of cancers, notably in several kidney-based malignancies. We synthesized, labeled, and assessed a series of radiotracers based on a previous high contrast PET imaging radiopharmaceutical [68Ga]Ga-BL02, with modifications to its linker and metal chelator, in order to improve its tumor-to-kidney contrast ratio. Methods: Based on the design of BL02, a piperidine-based cationic linker (BL06) and several anionic linkers (tri-Aad (BL17); tri-D-Glu (BL20); tri-Asp (BL25); and tri-cysteic acid (BL31)) were substituted for the triglutamate linker. Additionally, the DOTA chelator was swapped for a DOTAGA chelator (BL30). Each radiotracer was labeled with 68Ga and evaluated in CXCR4-expressing Daudi xenograft mice with biodistribution and/or PET imaging studies. Results: Of all the evaluated radiotracers, [68Ga]Ga-BL31 showed the most promising biodistribution profile, with a lower kidney uptake compared to [68Ga]Ga-BL02, while retaining the high imaging contrast capabilities of [68Ga]Ga-BL02. [68Ga]Ga-BL31 also compared favorably to [68Ga]Ga-Pentixafor, with superior imaging contrast in all non-target organs. The other anionic linker-based radiotracers showed either equivocal or worse contrast ratios compared to [68Ga]Ga-BL02; however, [68Ga]Ga-BL25 also showed lower kidney uptake, as compared to that of [68Ga]Ga-BL02. Meanwhile, [68Ga]Ga-BL06 had high non-target organ uptake and relatively lower tumor uptake, while [68Ga]Ga-BL30 showed significantly increased kidney uptake and similar tumor uptake values. Conclusions: [68Ga]Ga-BL31 is an optimized CXCR4-targeting radiopharmaceutical with lower kidney retention that has clinical potential for PET imaging and radioligand therapy.
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Affiliation(s)
- Daniel Kwon
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (D.K.); (Z.Z.); (J.Z.); (H.-T.K.); (K.-S.L.)
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (D.K.); (Z.Z.); (J.Z.); (H.-T.K.); (K.-S.L.)
| | - Jutta Zeisler
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (D.K.); (Z.Z.); (J.Z.); (H.-T.K.); (K.-S.L.)
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (D.K.); (Z.Z.); (J.Z.); (H.-T.K.); (K.-S.L.)
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (D.K.); (Z.Z.); (J.Z.); (H.-T.K.); (K.-S.L.)
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Francois Benard
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (D.K.); (Z.Z.); (J.Z.); (H.-T.K.); (K.-S.L.)
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Correspondence: ; Tel.: +1-604-675-8206
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21
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68Ga-Labeled [Leu 13ψThz 14]Bombesin(7-14) Derivatives: Promising GRPR-Targeting PET Tracers with Low Pancreas Uptake. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27123777. [PMID: 35744904 PMCID: PMC9230575 DOI: 10.3390/molecules27123777] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/06/2022] [Accepted: 06/09/2022] [Indexed: 11/16/2022]
Abstract
The gastrin-releasing peptide receptor (GRPR) is a G-protein-coupled receptor that is overexpressed in many solid cancers and is a promising target for cancer imaging and therapy. However, high pancreas uptake is a major concern in the application of reported GRPR-targeting radiopharmaceuticals, particularly for targeted radioligand therapy. To lower pancreas uptake, we explored Ga-complexed TacsBOMB2, TacsBOMB3, TacsBOMB4, TacsBOMB5, and TacsBOMB6 derived from a potent GRPR antagonist sequence, [Leu13ψThz14]Bombesin(7-14), and compared their potential for cancer imaging with [68Ga]Ga-RM2. The Ki(GRPR) values of Ga-TacsBOMB2, Ga-TacsBOMB3, Ga-TacsBOMB4, Ga-TacsBOMB5, Ga-TacsBOMB6, and Ga-RM2 were 7.08 ± 0.65, 4.29 ± 0.46, 458 ± 38.6, 6.09 ± 0.95, 5.12 ± 0.57, and 1.51 ± 0.24 nM, respectively. [68Ga]Ga-TacsBOMB2, [68Ga]Ga-TacsBOMB3, [68Ga]Ga-TacsBOMB5, [68Ga]Ga-TacsBOMB6, and [68Ga]Ga-RM2 clearly show PC-3 tumor xenografts in positron emission tomography (PET) images, while [68Ga]Ga-TacsBOMB5 shows the highest tumor uptake (15.7 ± 2.17 %ID/g) among them. Most importantly, the pancreas uptake values of [68Ga]Ga-TacsBOMB2 (2.81 ± 0.78 %ID/g), [68Ga]Ga-TacsBOMB3 (7.26 ± 1.00 %ID/g), [68Ga]Ga-TacsBOMB5 (1.98 ± 0.10 %ID/g), and [68Ga]Ga-TacsBOMB6 (6.50 ± 0.36 %ID/g) were much lower than the value of [68Ga]Ga-RM2 (41.9 ± 10.1 %ID/g). Among the tested [Leu13ψThz14]Bombesin(7-14) derivatives, [68Ga]Ga-TacsBOMB5 has the highest tumor uptake and tumor-to-background contrast ratios, which is promising for clinical translation to detect GRPR-expressing tumors. Due to the low pancreas uptake of its derivatives, [Leu13ψThz14]Bombesin(7-14) represents a promising pharmacophore for the design of GRPR-targeting radiopharmaceuticals, especially for targeted radioligand therapy application.
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PSMA-Targeting Imaging and Theranostic Agents-Current Status and Future Perspective. Int J Mol Sci 2022; 23:ijms23031158. [PMID: 35163083 PMCID: PMC8835702 DOI: 10.3390/ijms23031158] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/15/2022] [Accepted: 01/17/2022] [Indexed: 12/13/2022] Open
Abstract
In the past two decades, extensive efforts have been made to develop agents targeting prostate-specific membrane antigen (PSMA) for prostate cancer imaging and therapy. To date, represented by two recent approvals of [68Ga]Ga-PSMA-11 and [18F]F-DCFPyL by the United States Food and Drug Administration (US-FDA) for positron emission tomography (PET) imaging to identify suspected metastases or recurrence in patients with prostate cancer, PSMA-targeting imaging and theranostic agents derived from small molecule PSMA inhibitors have advanced to clinical practice and trials of prostate cancer. The focus of current development of new PSMA-targeting agents has thus shifted to the improvement of in vivo pharmacokinetics and higher specific binding affinity with the aims to further increase the detection sensitivity and specificity and minimize the toxicity to non-target tissues, particularly the kidneys. The main strategies involve systematic chemical modifications of the linkage between the targeting moiety and imaging/therapy payloads. In addition to a summary of the development history of PSMA-targeting agents, this review provides an overview of current advances and future promise of PSMA-targeted imaging and theranostics with focuses on the structural determinants of the chemical modification towards the next generation of PSMA-targeting agents.
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Plichta KA, Graves SA, Buatti JM. Prostate-Specific Membrane Antigen (PSMA) Theranostics for Treatment of Oligometastatic Prostate Cancer. Int J Mol Sci 2021; 22:12095. [PMID: 34829977 PMCID: PMC8621856 DOI: 10.3390/ijms222212095] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/01/2021] [Accepted: 11/06/2021] [Indexed: 11/17/2022] Open
Abstract
Theranostics, a combination of therapy and diagnostics, is a field of personalized medicine involving the use of the same or similar radiopharmaceutical agents for the diagnosis and treatment of patients. Prostate-specific membrane antigen (PSMA) is a promising theranostic target for the treatment of prostate cancers. Diagnostic PSMA radiopharmaceuticals are currently used for staging and diagnosis of prostate cancers, and imaging can predict response to therapeutic PSMA radiopharmaceuticals. While mainly used in the setting of metastatic, castrate-resistant disease, clinical trials are investigating the use of PSMA-based therapy at earlier stages, including in hormone-sensitive or hormone-naïve prostate cancers, and in oligometastatic prostate cancers. This review explores the use of PSMA as a theranostic target and investigates the potential use of PSMA in earlier stage disease, including hormone-sensitive metastatic prostate cancer, and oligometastatic prostate cancer.
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Affiliation(s)
- Kristin A. Plichta
- Department of Radiation Oncology, University of Iowa, LL-W PFP, 200 Hawkins Dr., Iowa City, IA 52242, USA; (S.A.G.); (J.M.B.)
| | - Stephen A. Graves
- Department of Radiation Oncology, University of Iowa, LL-W PFP, 200 Hawkins Dr., Iowa City, IA 52242, USA; (S.A.G.); (J.M.B.)
- Department of Radiology, University of Iowa, 3883 JPP, 200 Hawkins Dr., Iowa City, IA 52242, USA
| | - John M. Buatti
- Department of Radiation Oncology, University of Iowa, LL-W PFP, 200 Hawkins Dr., Iowa City, IA 52242, USA; (S.A.G.); (J.M.B.)
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Iikuni S, Tarumizu Y, Nakashima K, Higaki Y, Ichikawa H, Watanabe H, Ono M. Radiotheranostics Using a Novel 225Ac-Labeled Radioligand with Improved Pharmacokinetics Targeting Prostate-Specific Membrane Antigen. J Med Chem 2021; 64:13429-13438. [PMID: 34477385 DOI: 10.1021/acs.jmedchem.1c00772] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
225Ac-based radiotheranostics targeting prostate-specific membrane antigen (PSMA) has induced impressive responses in patients with metastatic castration-resistant prostate cancer. To enhance the therapeutic effects of radioligands labeled with 225Ac (half-life: 10 days), a radioligand that shows longer tumor retention would be useful. Here, we designed and synthesized a straight-chain PSMA-targeting radioligand, PSMA-DA1, which includes an (iodophenyl)butyric acid derivative as an albumin binder (ALB). We performed preclinical evaluations of PSMA-DA1 as a tool for PSMA-targeting radiotheranostics using 111In, 90Y, and 225Ac. [111In]In-PSMA-DA1 demonstrated significantly greater tumor uptake and retention than a corresponding non-ALB-conjugated compound. In mice, single-photon emission computed tomography performed with [111In]In-PSMA-DA1 produced clear tumor images, and the administration of [90Y]Y-PSMA-DA1 or [225Ac]Ac-PSMA-DA1 inhibited tumor growth. [225Ac]Ac-PSMA-DA1 had antitumor effects in mice at a lower radioactivity level than [225Ac]Ac-PSMA-617, which has been reported to be clinically useful. These results indicate that PSMA-DA1 may be a useful PSMA-targeting radiotheranostic agent.
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Affiliation(s)
- Shimpei Iikuni
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yuta Tarumizu
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kazuma Nakashima
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yusuke Higaki
- Nihon Medi-Physics Co., Ltd., 3-4-10 Shinsuna, Koto-ku, Tokyo 136-0075, Japan
| | - Hiroaki Ichikawa
- Nihon Medi-Physics Co., Ltd., 3-4-10 Shinsuna, Koto-ku, Tokyo 136-0075, Japan
| | - Hiroyuki Watanabe
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masahiro Ono
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
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El Fakiri M, Geis NM, Ayada N, Eder M, Eder AC. PSMA-Targeting Radiopharmaceuticals for Prostate Cancer Therapy: Recent Developments and Future Perspectives. Cancers (Basel) 2021; 13:cancers13163967. [PMID: 34439121 PMCID: PMC8393521 DOI: 10.3390/cancers13163967] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 07/22/2021] [Accepted: 07/28/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary One of the most frequently diagnosed cancer in men is adenocarcinoma of the prostate. Once the disease is metastatic, only very limited treatment options are available, resulting in a very short median survival time of 13 months; however, this reality is gradually changing due to the discovery of prostate-specific membrane antigen (PSMA), a protein that is present in cancerous prostate tissue. Researchers have developed pharmaceuticals specific for PSMA, ranging from antibodies (mAb) to low-molecular weight molecules coupled to beta minus and alpha-emitting radionuclides for their use in targeted radionuclide therapy (TRT). TRT offers the possibility of selectively removing cancer tissue via the emission of radiation or radioactive particles within the tumour. In this article, the major milestones in PSMA ligand research and the therapeutic developments are summarised, together with a future perspective on the enhancement of current therapeutic approaches. Abstract Prostate cancer (PC) is the second most common cancer among men, with 1.3 million yearly cases worldwide. Among those cancer-afflicted men, 30% will develop metastases and some will progress into metastatic castration-resistant prostate cancer (mCRPC), which is associated with a poor prognosis and median survival time that ranges from nine to 13 months. Nevertheless, the discovery of prostate specific membrane antigen (PSMA), a marker overexpressed in the majority of prostatic cancerous tissue, revolutionised PC care. Ever since, PSMA-targeted radionuclide therapy has gained remarkable international visibility in translational oncology. Furthermore, on first clinical application, it has shown significant influence on therapeutic management and patient care in metastatic and hormone-refractory prostate cancer, a disease that previously had remained immedicable. In this article, we provide a general overview of the main milestones in the development of ligands for PSMA-targeted radionuclide therapy, ranging from the firstly developed monoclonal antibodies to the current state-of-the-art low molecular weight entities conjugated with various radionuclides, as well as potential future efforts related to PSMA-targeted radionuclide therapy.
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Affiliation(s)
- Mohamed El Fakiri
- Department of Nuclear Medicine, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany; (M.E.F.); (N.M.G.); (N.A.); (A.-C.E.)
- Division of Radiopharmaceutical Development, German Cancer Consortium (DKTK), Partner Site Freiburg, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Nicolas M. Geis
- Department of Nuclear Medicine, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany; (M.E.F.); (N.M.G.); (N.A.); (A.-C.E.)
- Division of Radiopharmaceutical Development, German Cancer Consortium (DKTK), Partner Site Freiburg, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Nawal Ayada
- Department of Nuclear Medicine, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany; (M.E.F.); (N.M.G.); (N.A.); (A.-C.E.)
- Division of Radiopharmaceutical Development, German Cancer Consortium (DKTK), Partner Site Freiburg, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Matthias Eder
- Department of Nuclear Medicine, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany; (M.E.F.); (N.M.G.); (N.A.); (A.-C.E.)
- Division of Radiopharmaceutical Development, German Cancer Consortium (DKTK), Partner Site Freiburg, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Correspondence: ; Tel.: +49-761-270-74220
| | - Ann-Christin Eder
- Department of Nuclear Medicine, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany; (M.E.F.); (N.M.G.); (N.A.); (A.-C.E.)
- Division of Radiopharmaceutical Development, German Cancer Consortium (DKTK), Partner Site Freiburg, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
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Parsi M, Desai MH, Desai D, Singhal S, Khandwala PM, Potdar RR. PSMA: a game changer in the diagnosis and treatment of advanced prostate cancer. Med Oncol 2021; 38:89. [PMID: 34181109 DOI: 10.1007/s12032-021-01537-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 06/15/2021] [Indexed: 12/13/2022]
Abstract
Although management of advanced prostate cancer is evolving, a lot of work remains to be done for patients who have exhausted all options. Molecular targeting of prostate specific membrane antigen (PSMA) is valuable not only for diagnostic but also for therapeutic reasons. PSMA is thus considered to be useful in a theranostic approach. PSMA scans are upcoming diagnostic modalities which detect metastatic lesions that are missed by conventional imaging modalities. PSMA ligand therapy is also an upcoming treatment modality that has been proven to be beneficial with minimal toxicity in patients with advanced prostate cancer that have progressed on prior therapy. In this review article, we summarize the current knowledge regarding PSMA diagnostics and PSMA ligand therapies and discuss their implication in the treatment of advanced prostate cancer.
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Affiliation(s)
- Meghana Parsi
- Dept of Internal Medicine, Crozer-Chester Medical Center, 1 Medical Center Blvd, Upland, PA, USA.
| | - Milap H Desai
- Drexel University College of Medicine, Philadelphia, PA, USA
| | - Devashish Desai
- Dept of Internal Medicine, Crozer-Chester Medical Center, 1 Medical Center Blvd, Upland, PA, USA
| | - Sachi Singhal
- Dept of Internal Medicine, Crozer-Chester Medical Center, 1 Medical Center Blvd, Upland, PA, USA
| | - Pushti M Khandwala
- Dept of Internal Medicine, Crozer-Chester Medical Center, 1 Medical Center Blvd, Upland, PA, USA
| | - Rashmika R Potdar
- Dept of Hematology Oncology, Crozer-Chester Medical Center, Upland, PA, USA
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Ruigrok EAM, van Vliet N, Dalm SU, de Blois E, van Gent DC, Haeck J, de Ridder C, Stuurman D, Konijnenberg MW, van Weerden WM, de Jong M, Nonnekens J. Extensive preclinical evaluation of lutetium-177-labeled PSMA-specific tracers for prostate cancer radionuclide therapy. Eur J Nucl Med Mol Imaging 2021; 48:1339-1350. [PMID: 33094433 PMCID: PMC8113296 DOI: 10.1007/s00259-020-05057-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/24/2020] [Indexed: 01/13/2023]
Abstract
PURPOSE Various radiolabeled prostate-specific membrane antigen (PSMA)-targeting tracers are clinically applied for prostate cancer (PCa) imaging and targeted radionuclide therapy. The PSMA binding affinities, biodistribution, and DNA-damaging capacities of these radiotracers have not yet been compared in detail. A major concern of PSMA-targeting radiotracers is the toxicity in other PSMA-expressing organs, such as the salivary glands, thus demanding careful evaluation of the most optimal and safest radiotracer. In this extensive preclinical study, we evaluated the clinically applied PSMA-targeting small molecule inhibitors DOTA-PSMA-617 (PSMA-617) and DOTAGA-PSMA-I&T (PSMA-I&T) and the PSMA nanobody DOTA-JVZ-007 (JVZ-007) using PSMA-expressing cell lines, a unique set of PCa patient-derived xenografts (PDX) and healthy human tissues. METHODS AND RESULTS In vitro displacement studies on PSMA-expressing cells and cryosections of a PSMA-positive PDX revealed high and specific binding affinity for all three tracers labeled with lutetium-177 with IC50 values in the nanomolar range. Interestingly, [177Lu]Lu-JVZ-007 could not be displaced by PSMA-617 or PSMA-I&T, suggesting that this tracer targets an alternative binding site. Autoradiography assays on cryosections of human salivary and renal tissues revealed [177Lu]Lu-PSMA-617 to have the lowest binding to these healthy organs compared with [177Lu]Lu-PSMA-I&T. In vivo biodistribution assays confirmed the in vitro results with comparable tumor uptake of [177Lu]Lu-PSMA-617 and [177Lu]Lu-PSMA-I&T at all timepoints, resulting in induction of similar levels of DNA double-strand breaks in the tumors. However, [177Lu]Lu-PSMA-I&T demonstrated approximately 40× higher renal uptake at 4 and 8 h post injection resulting in an unfavorable tumor-to-kidney ratio. CONCLUSION [177Lu]Lu-PSMA-617 has the most favorable biodistribution in mice as well as more favorable binding characteristics in vitro in PSMA-positive cells and human kidney and salivary gland specimens compared with [177Lu]Lu-PSMA-I&T and [177Lu]Lu-JVZ-007. Based on our preclinical evaluation, [177Lu]Lu-PSMA-617 is the best performing tracer to be taken further into clinical evaluation for PSMA-targeted radiotherapeutic development although with careful evaluation of the tracer binding to PSMA-expressing organs.
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Affiliation(s)
- Eline A M Ruigrok
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
- Department of Experimental Urology, Erasmus MC, Rotterdam, The Netherlands
| | - Nicole van Vliet
- Department of Molecular Genetics, Erasmus MC, Rotterdam, The Netherlands
| | - Simone U Dalm
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Erik de Blois
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Dik C van Gent
- Department of Molecular Genetics, Erasmus MC, Rotterdam, The Netherlands
| | - Joost Haeck
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Corrina de Ridder
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
- Department of Experimental Urology, Erasmus MC, Rotterdam, The Netherlands
| | - Debra Stuurman
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
- Department of Experimental Urology, Erasmus MC, Rotterdam, The Netherlands
| | - Mark W Konijnenberg
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | | | - Marion de Jong
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Julie Nonnekens
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands.
- Department of Molecular Genetics, Erasmus MC, Rotterdam, The Netherlands.
- Oncode Institute, Erasmus MC, Rotterdam, The Netherlands.
- Erasmus MC, Room Ee757R, PO box 2040, 3000, CA, Rotterdam, The Netherlands.
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Ha H, Kwon H, Lim T, Jang J, Park SK, Byun Y. Inhibitors of prostate-specific membrane antigen in the diagnosis and therapy of metastatic prostate cancer - a review of patent literature. Expert Opin Ther Pat 2021; 31:525-547. [PMID: 33459068 DOI: 10.1080/13543776.2021.1878145] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
INTRODUCTION Prostate-specific membrane antigen (PSMA), also known as glutamate carboxypeptidase II, is a potential target protein for imaging and treatment of patients with prostate cancer because of its overexpression during metastasis. Various PSMA-targeted imaging and therapeutic probes have been designed and synthesized based on the Lys-urea-Glu motif. Structural modifications have been made exclusively in the linker region, while maintaining the Lys-urea-Glu structure that interacts with S1 and S1' pockets. AREA COVERED This review includes WIPO-listed patents (from January 2017 to June 2020) reporting PSMA-targeted probes based on the Lys-urea-Glu or Glu-urea-Glu structure. EXPERT OPINION : PSMA-targeted imaging agents labeled with radionuclides such as fluorine-18, copper-64, gallium-68, and technetium-99m have been successfully translated into clinical phase for the early diagnosis of metastatic prostate cancer. Recently, PSMA-targeted therapeutic agents labeled with iodine-131, lutetium-177, astatine-211, and lead-212 have also been developed with notable progress. Most PSMA-targeted agents are based on the Lys-urea-Glu or Glu-urea-Glu structure, demonstrate strong PSMA-binding affinity in nanomolar range, and achieve diverse structural modifications in the non-pharmacophore pocket. By exploiting the S1 accessory pocket or the tunnel region of the PSMA active site, the in vivo efficacy and pharmacokinetic profiles of the PMSA-targeted agents can be effectively modulated.
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Affiliation(s)
- Hyunsoo Ha
- Department of Pharmacy, College of Pharmacy, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea
| | - Hongmok Kwon
- Department of Pharmacy, College of Pharmacy, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea
| | - Taehyeong Lim
- Department of Pharmacy, College of Pharmacy, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea
| | - Jaebong Jang
- Department of Pharmacy, College of Pharmacy, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea
| | - Song-Kyu Park
- Department of Pharmacy, College of Pharmacy, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea
| | - Youngjoo Byun
- Department of Pharmacy, College of Pharmacy, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea
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Hall AJ, Haskali MB. Radiolabelled Peptides: Optimal Candidates for Theranostic Application in Oncology. Aust J Chem 2021. [DOI: 10.1071/ch21118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Kuo HT, Lin KS, Zhang Z, Uribe CF, Merkens H, Zhang C, Bénard F. 177Lu-Labeled Albumin-Binder-Conjugated PSMA-Targeting Agents with Extremely High Tumor Uptake and Enhanced Tumor-to-Kidney Absorbed Dose Ratio. J Nucl Med 2020; 62:521-527. [PMID: 32859704 DOI: 10.2967/jnumed.120.250738] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 07/29/2020] [Indexed: 12/22/2022] Open
Abstract
The use of an albumin binder has been shown to improve tumor uptake of prostate-specific membrane antigen (PSMA)-targeting radiotherapeutic agents. The aim of this study was to develop improved radiotherapeutic agents that combine an optimized affinity-modifying group and optimized albumin binders to maximize the tumor-to-kidney absorbed dose ratio. Methods: 68Ga-labeled DOTA-conjugated lysine-ureido-glutamate-based PSMA-targeting agents bearing various affinity-modifying groups or albumin binders were synthesized and evaluated by PET/CT imaging and biodistribution studies in LNCaP tumor-bearing mice. The optimized affinity-modifying group and albumin binders were combined, and the resulting derivatives were radiolabeled with 177Lu and evaluated by SPECT/CT imaging and biodistribution studies in LNCaP tumor-bearing mice. Radiation dosimetry was calculated using the OLINDA/EXM software. Results: Affinity-modifying group optimization revealed that 68Ga-HTK03041 bearing a tranexamic acid-9-anthrylalanine affinity-modifying group had the highest tumor uptake (23.1 ± 6.11 percentage injected dose [%ID]/g at 1 h after injection). Albumin binder optimization showed that 68Ga-HTK03055 and 68Ga-HTK03086 bearing the N-(4-(p-chlorophenyl)butanoyl)-Gly and N-(4-(p-methoxyphenyl)butanoyl)-Gly motifs, respectively, had relatively faster tumor accumulation (∼30 %ID/g at 3 h after injection) and lower average kidney uptake (<55 %ID/g at both 1 and 3 h after injection). Combining the tranexamic acid-9-anthrylalanine affinity-modifying group with N-(4-(p-chlorophenyl)butanoyl)-Gly and N-(4-(p-methoxyphenyl)butanoyl)-Gly albumin-binding motifs generated HTK03121 and HTK03123, respectively. 177Lu-HTK03121 and 177Lu-HTK03123 had extremely high peak uptake (104 ± 20.3 and 70.8 ± 23.7 %ID/g, respectively) in LNCaP tumor xenografts, and this peak was sustained up to 120 h after injection. Dosimetry calculation showed that compared with 177Lu-PSMA-617, 177Lu-HTK03121 and 177Lu-HTK03123 delivered 18.7- and 12.7-fold higher absorbed dose to tumor but only 6.4- and 6.3-fold higher absorbed dose to kidneys, leading to 2.9- and 2.0-fold improvement in the tumor-to-kidney absorbed dose ratios. Conclusion: With greatly enhanced tumor uptake and tumor-to-kidney absorbed dose ratio, 177Lu-HTK03121 and 177Lu-HTK03123 have the potential to improve treatment efficacy using significantly lower quantities of 177Lu and are promising candidates for clinical translation to treat metastatic castration-resistant prostate cancer.
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Affiliation(s)
- Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer, Vancouver, British Columbia, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer, Vancouver, British Columbia, Canada .,Department of Functional Imaging, BC Cancer, Vancouver, British Columbia, Canada; and.,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer, Vancouver, British Columbia, Canada
| | - Carlos F Uribe
- Department of Functional Imaging, BC Cancer, Vancouver, British Columbia, Canada; and
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer, Vancouver, British Columbia, Canada
| | - Chengcheng Zhang
- Department of Molecular Oncology, BC Cancer, Vancouver, British Columbia, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer, Vancouver, British Columbia, Canada.,Department of Functional Imaging, BC Cancer, Vancouver, British Columbia, Canada; and.,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
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Bendre S, Zhang Z, Kuo HT, Rousseau J, Zhang C, Merkens H, Roxin Á, Bénard F, Lin KS. Evaluation of Met-Val-Lys as a Renal Brush Border Enzyme-Cleavable Linker to Reduce Kidney Uptake of 68Ga-Labeled DOTA-Conjugated Peptides and Peptidomimetics. Molecules 2020; 25:molecules25173854. [PMID: 32854201 PMCID: PMC7503470 DOI: 10.3390/molecules25173854] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 08/17/2020] [Accepted: 08/21/2020] [Indexed: 12/24/2022] Open
Abstract
High kidney uptake is a common feature of peptide-based radiopharmaceuticals, leading to reduced detection sensitivity for lesions adjacent to kidneys and lower maximum tolerated therapeutic dose. In this study, we evaluated if the Met-Val-Lys (MVK) linker could be used to lower kidney uptake of 68Ga-labeled DOTA-conjugated peptides and peptidomimetics. A model compound, [68Ga]Ga-DOTA-AmBz-MVK(Ac)-OH (AmBz: aminomethylbenzoyl), and its derivative, [68Ga]Ga-DOTA-AmBz-MVK(HTK01166)-OH, coupled with the PSMA (prostate-specific membrane antigen)-targeting motif of the previously reported HTK01166 were synthesized and evaluated to determine if they could be recognized and cleaved by the renal brush border enzymes. Additionally, positron emission tomography (PET) imaging, ex vivo biodistribution and in vivo stability studies were conducted in mice to evaluate their pharmacokinetics. [68Ga]Ga-DOTA-AmBz-MVK(Ac)-OH was effectively cleaved specifically by neutral endopeptidase (NEP) of renal brush border enzymes at the Met-Val amide bond, and the radio-metabolite [68Ga]Ga-DOTA-AmBz-Met-OH was rapidly excreted via the renal pathway with minimal kidney retention. [68Ga]Ga-DOTA-AmBz-MVK(HTK01166)-OH retained its PSMA-targeting capability and was also cleaved by NEP, although less effectively when compared to [68Ga]Ga-DOTA-AmBz-MVK(Ac)-OH. The kidney uptake of [68Ga]Ga-DOTA-AmBz-MVK(HTK01166)-OH was 30% less compared to that of [68Ga]Ga-HTK01166. Our data demonstrated that derivatives of [68Ga]Ga-DOTA-AmBz-MVK-OH can be cleaved specifically by NEP, and therefore, MVK can be a promising cleavable linker for use to reduce kidney uptake of radiolabeled DOTA-conjugated peptides and peptidomimetics.
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Affiliation(s)
- Shreya Bendre
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
| | - Julie Rousseau
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
| | - Chengcheng Zhang
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
| | - Áron Roxin
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
| | - François Bénard
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
- Department of Functional Imaging, BC Cancer, Vancouver, BC V5Z 4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer, Vancouver, BC V5Z 1L3, Canada; (S.B.); (Z.Z.); (H.-T.K.); (J.R.); (C.Z.); (H.M.); (Á.R.); (F.B.)
- Department of Functional Imaging, BC Cancer, Vancouver, BC V5Z 4E6, Canada
- Department of Radiology, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Correspondence:
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Li L, Kuo HT, Wang X, Merkens H, Colpo N, Radchenko V, Schaffer P, Lin KS, Bénard F, Orvig C. tBu 4octapa-alkyl-NHS for metalloradiopeptide preparation. Dalton Trans 2020; 49:7605-7619. [PMID: 32459231 DOI: 10.1039/d0dt00845a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The peptide is an important class of biological targeting molecule; herein, a new bifunctional octadentate non-macrocyclic H4octapa, tBu4octapa-alkyl-NHS, which is compatible with solid-phase peptide synthesis and thus useful for radiopeptide preparation, has been synthesized. To preserve denticity, the alkyl-N-hydroxylsuccinimide linker was covalently attached to the methylene-carbon on one of the acetate arms, yielding a chiral carbon center. According to density-functional theory (DFT) calculations using [Lu(octapa-alkyl-benzyl-ester)]- as a simulation model, the chirality has minimal effects on the complex geometry; regardless of the S-/R-stereochemistry, DFT calculations revealed two possible geometric isomers, distorted bicapped trigonal antiprism (DBTA) and distorted square antiprism (DSA), due to the asymmetry in the chelator. To evaluate the biological behavior of the new bifunctionalization, two well-studied PSMA (prostate-specific membrane antigen)-targeting peptidomimetics of varying hydrophobicity were chosen as proof-of-principle targeting vector molecules. Radiolabeling both bioconjugates with lutetium-177 was highly efficient at room temperature in 15 min at micromolar chelator concentration pH = 7. Both the in vitro serum challenge and the lanthanum(iii) challenge studies revealed complex lability, and notably, progressive bone accumulation was only observed with the more hydrophobic linker (i.e. H4octapa-alkyl-PSMA617). This in vivo result informs potential alterations exerted by the linker on the complex geometry and stability, with an appropriate biological targeting vector adopted for such evaluations.
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Affiliation(s)
- Lily Li
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada. and Life Sciences Division, TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer, 675 West 10th Ave, Vancouver, British Columbia V5Z 1L3, Canada
| | - Xiaozhu Wang
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer, 675 West 10th Ave, Vancouver, British Columbia V5Z 1L3, Canada
| | - Nadine Colpo
- Department of Molecular Oncology, BC Cancer, 675 West 10th Ave, Vancouver, British Columbia V5Z 1L3, Canada
| | - Valery Radchenko
- Life Sciences Division, TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada and Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6 T 1Z1, Canada
| | - Paul Schaffer
- Life Sciences Division, TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer, 675 West 10th Ave, Vancouver, British Columbia V5Z 1L3, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer, 675 West 10th Ave, Vancouver, British Columbia V5Z 1L3, Canada
| | - Chris Orvig
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.
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Winter G, Koch ABF, Löffler J, Lindén M, Solbach C, Abaei A, Li H, Glatting G, Beer AJ, Rasche V. Multi-Modal PET and MR Imaging in the Hen's Egg Test-Chorioallantoic Membrane (HET-CAM) Model for Initial in Vivo Testing of Target-Specific Radioligands. Cancers (Basel) 2020; 12:cancers12051248. [PMID: 32429233 PMCID: PMC7281765 DOI: 10.3390/cancers12051248] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 12/17/2022] Open
Abstract
The validation of novel target-specific radioligands requires animal experiments mostly using mice with xenografts. A pre-selection based on a simpler in vivo model would allow to reduce the number of animal experiments, in accordance with the 3Rs principles (reduction, replacement, refinement). In this respect, the chick embryo or hen’s egg test–chorioallantoic membrane (HET-CAM) model is of special interest, as it is not considered an animal until day 17. Thus, we evaluated the feasibility of quantitative analysis of target-specific radiotracer accumulation in xenografts using the HET-CAM model and combined positron emission tomography (PET) and magnetic resonance imaging (MRI). For proof-of-principle we used established prostate-specific membrane antigen (PSMA)-positive and PSMA-negative prostate cancer xenografts and the clinically widely used PSMA-specific PET-tracer [68Ga]Ga-PSMA-11. Tracer accumulation was quantified by PET and tumor volumes measured with MRI (n = 42). Moreover, gamma-counter analysis of radiotracer accumulation was done ex-vivo. A three- to five-fold higher ligand accumulation in the PSMA-positive tumors compared to the PSMA-negative tumors was demonstrated. This proof-of-principle study shows the general feasibility of the HET-CAM xenograft model for target-specific imaging with PET and MRI. The ultimate value for characterization of novel target-specific radioligands now has to be validated in comparison to mouse xenograft experiments.
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Affiliation(s)
- Gordon Winter
- Department of Nuclear Medicine, Ulm University Medical Center, 89081 Ulm, Germany; (A.B.F.K.); (J.L.); (C.S.); (A.J.B.)
- Correspondence: (G.W.); (V.R.); Tel.: +49-731-500-61364 (G.W.); +49-731-500-45014 (V.R.)
| | - Andrea B. F. Koch
- Department of Nuclear Medicine, Ulm University Medical Center, 89081 Ulm, Germany; (A.B.F.K.); (J.L.); (C.S.); (A.J.B.)
| | - Jessica Löffler
- Department of Nuclear Medicine, Ulm University Medical Center, 89081 Ulm, Germany; (A.B.F.K.); (J.L.); (C.S.); (A.J.B.)
- Core Facility Small Animal Imaging, Ulm University Medical Center, 89081 Ulm, Germany; (A.A.); (H.L.)
| | - Mika Lindén
- Department of Inorganic Chemistry II, Ulm University, 89081 Ulm, Germany;
| | - Christoph Solbach
- Department of Nuclear Medicine, Ulm University Medical Center, 89081 Ulm, Germany; (A.B.F.K.); (J.L.); (C.S.); (A.J.B.)
| | - Alireza Abaei
- Core Facility Small Animal Imaging, Ulm University Medical Center, 89081 Ulm, Germany; (A.A.); (H.L.)
| | - Hao Li
- Core Facility Small Animal Imaging, Ulm University Medical Center, 89081 Ulm, Germany; (A.A.); (H.L.)
| | - Gerhard Glatting
- Department of Nuclear Medicine, Medical Radiation Physics, Ulm University Medical Center, 89081 Ulm, Germany;
| | - Ambros J. Beer
- Department of Nuclear Medicine, Ulm University Medical Center, 89081 Ulm, Germany; (A.B.F.K.); (J.L.); (C.S.); (A.J.B.)
| | - Volker Rasche
- Core Facility Small Animal Imaging, Ulm University Medical Center, 89081 Ulm, Germany; (A.A.); (H.L.)
- Internal Medicine II, Ulm University Medical Center, 89081 Ulm, Germany
- Correspondence: (G.W.); (V.R.); Tel.: +49-731-500-61364 (G.W.); +49-731-500-45014 (V.R.)
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Li Y, Chyan MK, Hamlin DK, Nguyen H, Vessella R, Wilbur DS. Evaluation of radioiodinated protein conjugates and their potential metabolites containing lysine-urea-glutamate (LuG), PEG and closo-decaborate(2-) as models for targeting astatine-211 to metastatic prostate cancer. Nucl Med Biol 2020; 92:217-227. [PMID: 32409263 DOI: 10.1016/j.nucmedbio.2020.04.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Accepted: 04/29/2020] [Indexed: 12/18/2022]
Abstract
INTRODUCTION The use of lysine-urea-glutamate (LuG) for targeting the PSMA antigen on prostate cancer (PCa) is a promising method for delivering the alpha particle-emitting radionuclide astatine-211 (211At) to metastatic PCa. High kidney localization has been a problem with radiolabeled LuG derivatives, but has been adequately addressed in radiometal-labeled DOTA-LuG derivatives by linker optimization. Herein, we report an investigation of an alternate approach to diminishing the kidney concentrations of radiolabeled LuG-containing compounds. METHODS Our approach involves PEGylated LuG moieties and closo-decaborate (2-) moieties conjugated to streptavidin (SAv) or human serum albumin (HSA). After preparing the LuG conjugates, SAv and HSA conjugates were succinylated to decrease their kidney localization and radioiodinated for evaluation in athymic mice bearing C4-2B osseous PCa tumor xenografts. RESULTS Covalently attaching LuG to succinylated SAv and HSA significantly reduced kidney localization, but unfortunately succinylation resulted in decreased tumor concentrations. In contrast, a potential metabolite [131I]16b, an unconjugated LuG derivative containing a dPEG4® linker, provided tumor concentrations of ~15% ID/g at 4 h pi. A second unconjugated LuG derivative with a similar structure, but containing a dPEG12® linker, [131I]16a had tumor concentrations of ~4%ID/g at 4 h pi. Those results suggest that long PEG linkers also affect tumor localization in a negative manner. CONCLUSION Conjugation of PEGylated LuG derivatives to proteins can be an effective approach to diminishing kidney localization of radiolabeled LuG reagents, but the protein, linker and the method of linkage need to be further studied. Additionally, modification of the unconjugated 16b to decrease kidney localization may provide PCa targeting agents for use with radiohalogens, including 211At. Advances in knowledge and implications for patient care: This study is the first to evaluate PEGylated LuG and closo-decaborate (2-) moieties conjugated to proteins as potential methods for diminishing the kidney concentrations of radiolabeled LuG-containing compounds.
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Affiliation(s)
- Yawen Li
- Radiochemistry Division, Department of Radiation Oncology, University of Washington, Seattle, WA 98105, United States of America
| | - Ming-Kuan Chyan
- Radiochemistry Division, Department of Radiation Oncology, University of Washington, Seattle, WA 98105, United States of America
| | - Donald K Hamlin
- Radiochemistry Division, Department of Radiation Oncology, University of Washington, Seattle, WA 98105, United States of America
| | - Holly Nguyen
- GU Cancer Research Lab, Department of Urology, University of Washington, Seattle, WA 98195, United States of America
| | - Robert Vessella
- GU Cancer Research Lab, Department of Urology, University of Washington, Seattle, WA 98195, United States of America
| | - D Scott Wilbur
- Radiochemistry Division, Department of Radiation Oncology, University of Washington, Seattle, WA 98105, United States of America.
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Stenberg VY, Juzeniene A, Chen Q, Yang X, Bruland ØS, Larsen RH. Preparation of the alpha-emitting prostate-specific membrane antigen targeted radioligand [ 212 Pb]Pb-NG001 for prostate cancer. J Labelled Comp Radiopharm 2020; 63:129-143. [PMID: 31919866 DOI: 10.1002/jlcr.3825] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/17/2019] [Accepted: 01/06/2020] [Indexed: 12/26/2022]
Abstract
Prostate-specific membrane antigen (PSMA) is the most promising target for radioligand therapy of prostate cancer. The aim of this study was to prepare a small molecular ligand p-SCN-Bn-TCMC-PSMA (NG001) and compare it with the commonly used DOTA-based PSMA-617. The PSMA-targeting ability of the 212 Pb-labelled ligands was evaluated using PSMA-positive C4-2 human prostate cancer cells. Lead-212 is an in vivo generator of alpha particles by its daughter nuclides 212 Bi and 212 Po. NG001 was synthesized by conjugating the isothiocyanato group of p-SCN-Bn-TCMC to the amino group of a glutamate-urea-based PSMA-binding entity. Molecular size, chelator unit and chelator linking method are different in NG001 and PSMA-617. Both ligands were efficiently labelled with 212 Pb using a 224 Ra/212 Pb-solution generator in transient equilibrium with progeny. Lead-212-labelled NG001 was purified with a yield of 85.9±4.7% and with 0.7±0.2% of 224 Ra. Compared with [212 Pb]Pb-PSMA-617, [212 Pb]Pb-NG001 displayed a similar binding and internalization in C4-2 cells, with comparable tumour uptake in mice bearing C4-2 tumours, but almost a 2.5-fold lower kidney uptake. Due to the rapid normal tissue clearance and tumour cell internalization, any significant translocalization of 212 Bi was not detected in mice. In conclusion, the obtained results warrant further preclinical studies to evaluate the therapeutic efficacy of [212 Pb]Pb-NG001.
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Affiliation(s)
- Vilde Yuli Stenberg
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.,Department of Research and Development, Nucligen AS, Oslo, Norway.,Institute for Clinical Medicine, University of Oslo, Oslo, Norway
| | - Asta Juzeniene
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Qingqi Chen
- Department of Drug Synthesis, MedKoo Biosciences, Morrisville, North Carolina
| | - Xiaoming Yang
- Department of Drug Synthesis, MedKoo Biosciences, Morrisville, North Carolina
| | - Øyvind Sverre Bruland
- Institute for Clinical Medicine, University of Oslo, Oslo, Norway.,Department of Oncology, Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
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Synthesis and Evaluation of 99mTc-Tricabonyl Labeled Isonitrile Conjugates for Prostate-Specific Membrane Antigen (PSMA) Image. INORGANICS 2020. [DOI: 10.3390/inorganics8010005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Prostate-specific membrane antigen (PSMA) is a biomarker expressed on the surface of prostate cancer (PCa). In an effort to improve the detection and treatment of PCa, small urea-based PSMA inhibitors have been studied extensively. In the present study, we aimed to develop 99mTc-tricabonyl labeled urea-based PSMA conjugates containing isonitrile (CN-R)-coordinating ligands ([99mTc]Tc-15 and [99mTc]Tc-16). Both the PSMA conjugates were obtained at high radiochemical efficiency (≥98.5%). High in vitro binding affinity was observed for [99mTc]Tc-15 and [99mTc]Tc-16 (Kd = 5.5 and 0.2 nM, respectively) in PSMA-expressing 22Rv1 cells. Tumor xenografts were conducted using 22Rv1 cells and rapid accumulation of [99mTc]Tc-16 (1.87 ± 0.11% ID/g) was observed at 1 h post-injection, which subsequently increased to (2.83 ± 0.26% ID/g) at 4 h post-injection. However, [99mTc]Tc-15 showed moderate tumor uptake (1.48 ± 0.18% ID/g), which decreased at 4 h post-injection (0.81 ± 0.09% ID/g). [99mTc]Tc-16 was excreted from non-targeted tissues with high tumor-to-blood (17:1) and tumor-to-muscle ratio (41:1) at 4 h post-injection at approximately 4 times higher levels than [99mTc]Tc-15. Uptakes of [99mTc]Tc-15 and [99mTc]Tc-16 to PSMA-expressing tumor and tissues were significantly blocked by co-injection of 2-(Phosphonomethyl)-pentandioic acid (2-PMPA), suggesting that their uptakes are mediated by PSMA specifically. Whole-body single photon emission computed tomography imaging of [99mTc]Tc-16 verified the ex vivo biodistribution results and demonstrated clear visualization of tumors and tissues expressing PSMA compared to [99mTc]Tc-15. In conclusion, using [99mTc]Tc-16 rather than [99mTc]Tc-15 may be the preferable because of its relatively high tumor uptake and retention.
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Li M, Sagastume EE, Lee D, McAlister D, DeGraffenreid AJ, Olewine KR, Graves S, Copping R, Mirzadeh S, Zimmerman BE, Larsen R, Johnson FL, Schultz MK. 203/212Pb Theranostic Radiopharmaceuticals for Image-guided Radionuclide Therapy for Cancer. Curr Med Chem 2020; 27:7003-7031. [PMID: 32720598 PMCID: PMC10613023 DOI: 10.2174/0929867327999200727190423] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/25/2020] [Accepted: 04/15/2020] [Indexed: 02/07/2023]
Abstract
Receptor-targeted image-guided Radionuclide Therapy (TRT) is increasingly recognized as a promising approach to cancer treatment. In particular, the potential for clinical translation of receptor-targeted alpha-particle therapy is receiving considerable attention as an approach that can improve outcomes for cancer patients. Higher Linear-energy Transfer (LET) of alpha-particles (compared to beta particles) for this purpose results in an increased incidence of double-strand DNA breaks and improved-localized cancer-cell damage. Recent clinical studies provide compelling evidence that alpha-TRT has the potential to deliver a significantly more potent anti-cancer effect compared with beta-TRT. Generator-produced 212Pb (which decays to alpha emitters 212Bi and 212Po) is a particularly promising radionuclide for receptor-targeted alpha-particle therapy. A second attractive feature that distinguishes 212Pb alpha-TRT from other available radionuclides is the possibility to employ elementallymatched isotope 203Pb as an imaging surrogate in place of the therapeutic radionuclide. As direct non-invasive measurement of alpha-particle emissions cannot be conducted using current medical scanner technology, the imaging surrogate allows for a pharmacologically-inactive determination of the pharmacokinetics and biodistribution of TRT candidate ligands in advance of treatment. Thus, elementally-matched 203Pb labeled radiopharmaceuticals can be used to identify patients who may benefit from 212Pb alpha-TRT and apply appropriate dosimetry and treatment planning in advance of the therapy. In this review, we provide a brief history on the use of these isotopes for cancer therapy; describe the decay and chemical characteristics of 203/212Pb for their use in cancer theranostics and methodologies applied for production and purification of these isotopes for radiopharmaceutical production. In addition, a medical physics and dosimetry perspective is provided that highlights the potential of 212Pb for alpha-TRT and the expected safety for 203Pb surrogate imaging. Recent and current preclinical and clinical studies are presented. The sum of the findings herein and observations presented provide evidence that the 203Pb/212Pb theranostic pair has a promising future for use in radiopharmaceutical theranostic therapies for cancer.
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Affiliation(s)
- Mengshi Li
- Department of Radiology, The University of Iowa, Iowa City, IA USA
- Viewpoint Molecular Targeting, Inc., Coralville, IA USA
| | | | - Dongyoul Lee
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA
| | | | | | | | - Stephen Graves
- Department of Radiology, The University of Iowa, Iowa City, IA USA
| | - Roy Copping
- Oak Ridge National Laboratory, The US Department of Energy, Oak Ridge TN USA
| | - Saed Mirzadeh
- Oak Ridge National Laboratory, The US Department of Energy, Oak Ridge TN USA
| | - Brian E. Zimmerman
- The National Institute of Standards and Technology, Gaithersburg, MD, USA
| | | | - Frances L. Johnson
- Viewpoint Molecular Targeting, Inc., Coralville, IA USA
- Department of Internal Medicine, Carver College of Medicine, The University of Iowa, Iowa City, Iowa USA
| | - Michael K. Schultz
- Department of Radiology, The University of Iowa, Iowa City, IA USA
- Viewpoint Molecular Targeting, Inc., Coralville, IA USA
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA
- Department of Chemistry, The University of Iowa, Iowa City, IA, USA
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Ruigrok EAM, van Weerden WM, Nonnekens J, de Jong M. The Future of PSMA-Targeted Radionuclide Therapy: An Overview of Recent Preclinical Research. Pharmaceutics 2019; 11:E560. [PMID: 31671763 PMCID: PMC6921028 DOI: 10.3390/pharmaceutics11110560] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 12/15/2022] Open
Abstract
Prostate specific membrane antigen (PSMA) has become a major focus point in the research and development of prostate cancer (PCa) imaging and therapeutic strategies using radiolabeled tracers. PSMA has shown to be an excellent target for PCa theranostics because of its high expression on the membrane of PCa cells and the increase in expression during disease progression. Therefore, numerous PSMA-targeting tracers have been developed and (pre)clinically studied with promising results. However, many of these PSMA-targeting tracers show uptake in healthy organs such as the salivary glands, causing radiotoxicity. Furthermore, not all patients respond to PSMA-targeted radionuclide therapy (TRT). This created the necessity of additional preclinical research studies in which existing tracers are reevaluated and new tracers are developed in order to improve PSMA-TRT by protecting the (PSMA-expressing) healthy organs and improving tumor uptake. In this review we will give an overview of the recent preclinical research projects regarding PCa-TRT using PSMA-specific radiotracers, which will give an indication of where the PSMA-TRT research movement is going and what we can expect in future clinical trials.
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Affiliation(s)
- Eline A M Ruigrok
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Dept. of Experimental Urology, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | | | - Julie Nonnekens
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Dept. of Molecular Genetics, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Oncode Institute, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | - Marion de Jong
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
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Hensbergen AW, Buckle T, van Willigen DM, Schottelius M, Welling MM, van der Wijk FA, Maurer T, van der Poel HG, van der Pluijm G, van Weerden WM, Wester HJ, van Leeuwen FWB. Hybrid Tracers Based on Cyanine Backbones Targeting Prostate-Specific Membrane Antigen: Tuning Pharmacokinetic Properties and Exploring Dye-Protein Interaction. J Nucl Med 2019; 61:234-241. [PMID: 31481575 DOI: 10.2967/jnumed.119.233064] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 08/06/2019] [Indexed: 12/14/2022] Open
Abstract
Prostate cancer surgery is currently being revolutionized by the use of prostate-specific membrane antigen (PSMA)-targeted radiotracers, for example, 99mTc-labeled PSMA tracer analogs for radioguided surgery. The purpose of this study was to develop a second-generation 99mTc-labeled PSMA-targeted tracer incorporating a fluorescent dye. Methods: Several PSMA-targeted hybrid tracers were synthesized: glutamic acid-urea-lysine (EuK)-Cy5-mas3, EuK-(SO3)Cy5-mas3, EuK-Cy5(SO3)-mas3, EuK-(Ar)Cy5-mas3, and EuK-Cy5(Ar)-mas3; the Cy5 dye acts as a functional backbone between the EuK targeting vector and the 2-mercaptoacetyl-seryl-seryl-seryl (mas3) chelate to study the dye's interaction with PSMA's amphipathic entrance funnel. The compounds were evaluated for their photophysical and chemical properties and PSMA affinity. After radiolabeling with 99mTc, we performed in vivo SPECT imaging, biodistribution, and fluorescence imaging on BALB/c nude mice with orthotopically transplanted PC346C tumors. Results: The dye composition influenced the photophysical properties (brightness range 0.3-1.5 × 104 M-1 × cm-1), plasma protein interactions (range 85.0% ± 2.3%-90.7% ± 1.3% bound to serum, range 76% ± 0%-89% ± 6% stability in serum), PSMA affinity (half-maximal inhibitory concentration [IC50] range 19.2 ± 5.8-175.3 ± 61.1 nM) and in vivo characteristics (tumor-to-prostate and tumor-to-muscle ratios range 0.02 ± 0.00-154.73 ± 28.48 and 0.46 ± 0.28-5,157.50 ± 949.17, respectively; renal, splenic, and salivary retention). Even though all tracer analogs allowed tumor identification with SPECT and fluorescence imaging, 99mTc-EuK-(SO3)Cy5-mas3 had the most promising properties (e.g., half-maximal inhibitory concentration, 19.2 ± 5.8, tumor-to-muscle ratio, 5,157.50 ± 949.17). Conclusion: Our findings demonstrate the intrinsic integration of a fluorophore in the pharmacophore in PSMA-targeted small-molecule tracers. In this design, having 1 sulfonate on the indole moiety adjacent to EuK (99mTc-EuK-(SO3)Cy5-mas3) yielded the most promising tracer candidate for imaging of PSMA.
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Affiliation(s)
- Albertus W Hensbergen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Tessa Buckle
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Danny M van Willigen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Margret Schottelius
- Pharmazeutische Radiochemie, Technische Universität München, Garching, Germany
| | - Mick M Welling
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Felicia A van der Wijk
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Tobias Maurer
- Martini-Klinik, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Henk G van der Poel
- Department of Urology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands
| | - Gabri van der Pluijm
- Department of Urology, Leiden University Medical Centre, Leiden, The Netherlands; and
| | - Wytske M van Weerden
- Department of Urology, Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Hans-Jürgen Wester
- Pharmazeutische Radiochemie, Technische Universität München, Garching, Germany
| | - Fijs W B van Leeuwen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
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40
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Li L, Jaraquemada-Peláez MDG, Kuo HT, Merkens H, Choudhary N, Gitschtaler K, Jermilova U, Colpo N, Uribe-Munoz C, Radchenko V, Schaffer P, Lin KS, Bénard F, Orvig C. Functionally Versatile and Highly Stable Chelator for 111In and 177Lu: Proof-of-Principle Prostate-Specific Membrane Antigen Targeting. Bioconjug Chem 2019; 30:1539-1553. [PMID: 31009566 DOI: 10.1021/acs.bioconjchem.9b00225] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Here, we present the synthesis and characterization of a new potentially nonadentate chelator H4pypa and its bifunctional analogue tBu4pypa-C7-NHS conjugated to prostate-specific membrane antigen (PSMA)-targeting peptidomimetic (Glu-urea-Lys). H4pypa is very functionally versatile and biologically stable. Compared to the conventional chelators (e.g., DOTA, DTPA), H4pypa has outstanding affinities for both 111In (EC, t1/2 ≈ 2.8 days) and 177Lu (β-,γ, t1/2 ≈ 6.64 days). Its radiolabeled complexes were achieved at >98% radiochemical yield, RT within 10 min, at a ligand concentration as low as 10-6 M, with excellent stability in human serum over at least 5-7 days (<1% transchelation). The thermodynamic stabilities of the [M(pypa)]- complexes (M3+ = In3+, Lu3+, La3+) were dependent on the ionic radii, where the smaller In3+ has the highest pM value (30.5), followed by Lu3+ (22.6) and La3+ (19.9). All pM values are remarkably higher than those with DOTA, DTPA, H4octapa, H4octox, and H4neunpa. Moreover, the facile and versatile bifunctionalization enabled by the p-OH group in the central pyridyl bridge of the pypa scaffold (compound 14) allows incorporation of a variety of linkers for bioconjugation through easy nucleophilic substitution. In this work, an alkyl linker was selected to couple H4pypa to a PSMA-targeting pharmacophore, proving that the bioconjugation sacrifices neither the tumor-targeting nor the chelation properties. The biodistribution profiles of 111In- and 177Lu-labeled tracers are different, but promising, with the 177Lu analogue particularly outstanding.
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Affiliation(s)
- Lily Li
- Life Sciences Division , TRIUMF , 4004 Wesbrook Mall , Vancouver , British Columbia V6T 2A3 , Canada
| | | | - Hsiou-Ting Kuo
- Department of Molecular Oncology , BC Cancer , 675 West 10th Avenue , Vancouver , British Columbia V5Z 1L3 , Canada
| | - Helen Merkens
- Department of Molecular Oncology , BC Cancer , 675 West 10th Avenue , Vancouver , British Columbia V5Z 1L3 , Canada
| | - Neha Choudhary
- Life Sciences Division , TRIUMF , 4004 Wesbrook Mall , Vancouver , British Columbia V6T 2A3 , Canada
| | - Katrin Gitschtaler
- Department of Molecular Oncology , BC Cancer , 675 West 10th Avenue , Vancouver , British Columbia V5Z 1L3 , Canada
| | | | - Nadine Colpo
- Department of Molecular Oncology , BC Cancer , 675 West 10th Avenue , Vancouver , British Columbia V5Z 1L3 , Canada
| | - Carlos Uribe-Munoz
- Department of Molecular Oncology , BC Cancer , 675 West 10th Avenue , Vancouver , British Columbia V5Z 1L3 , Canada
| | - Valery Radchenko
- Life Sciences Division , TRIUMF , 4004 Wesbrook Mall , Vancouver , British Columbia V6T 2A3 , Canada
| | - Paul Schaffer
- Life Sciences Division , TRIUMF , 4004 Wesbrook Mall , Vancouver , British Columbia V6T 2A3 , Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology , BC Cancer , 675 West 10th Avenue , Vancouver , British Columbia V5Z 1L3 , Canada
| | - François Bénard
- Department of Molecular Oncology , BC Cancer , 675 West 10th Avenue , Vancouver , British Columbia V5Z 1L3 , Canada
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41
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Kuo HT, Lepage ML, Lin KS, Pan J, Zhang Z, Liu Z, Pryyma A, Zhang C, Merkens H, Roxin A, Perrin DM, Bénard F. One-Step 18F-Labeling and Preclinical Evaluation of Prostate-Specific Membrane Antigen Trifluoroborate Probes for Cancer Imaging. J Nucl Med 2019; 60:1160-1166. [PMID: 30737299 PMCID: PMC6681697 DOI: 10.2967/jnumed.118.216598] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 01/13/2019] [Indexed: 01/28/2023] Open
Abstract
After the identification of the high-affinity glutamate-ureido scaffold, the design of several potent 18F- and 68Ga-labeled tracers has allowed spectacular progress in imaging recurrent prostate cancer by targeting the prostate-specific membrane antigen (PSMA). We evaluated a series of PSMA-targeting probes that are 18F-labeled in a single step for PET imaging of prostate cancer. Methods: We prepared 8 trifluoroborate constructs for prostate cancer imaging, to study the influence of the linker and the trifluoroborate prosthetic on pharmacokinetics and image quality. After 1-step labeling by 19F-18F isotopic exchange, the radiotracers were injected in mice bearing LNCaP xenografts, with or without blocking controls, to assess specific uptake. PET/CT images and biodistribution data were acquired at 1 h after injection and compared with 18F-DCFPyL on the same mouse strain and tumor model. Results: All tracers exhibited nanomolar affinities, were labeled in good radiochemical yields at high molar activities, and exhibited high tumor uptake in LNCaP xenografts with clearance from nontarget organs. Most derivatives with a naphthylalanine linker showed significant gastrointestinal excretion. A radiotracer incorporating this linker with a dual trifluoroborate-glutamate labeling moiety showed high tumor uptake, low background activity, and no liver or gastrointestinal track accumulation. Conclusion: PSMA-targeting probes with trifluoroborate prosthetic groups represent promising candidates for prostate cancer imaging because of facile labeling while affording high tumor uptake values and contrast ratios that are similar to those obtained with 18F-DCFPyL.
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Affiliation(s)
- Hsiou-Ting Kuo
- BC Cancer, Vancouver, British Columbia, Canada.,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Mathieu L Lepage
- Chemistry Department, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kuo-Shyan Lin
- BC Cancer, Vancouver, British Columbia, Canada .,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Jinhe Pan
- BC Cancer, Vancouver, British Columbia, Canada
| | | | - Zhibo Liu
- Chemistry Department, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alla Pryyma
- Chemistry Department, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Helen Merkens
- BC Cancer, Vancouver, British Columbia, Canada.,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Aron Roxin
- BC Cancer, Vancouver, British Columbia, Canada.,Chemistry Department, University of British Columbia, Vancouver, British Columbia, Canada
| | - David M Perrin
- Chemistry Department, University of British Columbia, Vancouver, British Columbia, Canada
| | - François Bénard
- BC Cancer, Vancouver, British Columbia, Canada .,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada; and
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42
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Rousseau E, Lau J, Kuo HT, Zhang Z, Merkens H, Hundal-Jabal N, Colpo N, Lin KS, Bénard F. Monosodium Glutamate Reduces 68Ga-PSMA-11 Uptake in Salivary Glands and Kidneys in a Preclinical Prostate Cancer Model. J Nucl Med 2018; 59:1865-1868. [PMID: 30097503 PMCID: PMC6278899 DOI: 10.2967/jnumed.118.215350] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/20/2018] [Indexed: 01/28/2023] Open
Abstract
We evaluated the ability of monosodium glutamate (MSG) to reduce salivary and kidney uptake of a prostate-specific membrane antigen (PSMA) radioligand without affecting tumor uptake. Methods: LNCaP tumor-bearing mice were intraperitoneally injected with MSG (657, 329, or 164 mg/kg) or phosphate-buffered saline (PBS). Fifteen minutes later, the mice were intravenously administered 68Ga-PSMA-11. PET/CT imaging and biodistribution studies were performed 1 h after administration. Results: Tumor uptake (percentage injected dose per gram [%ID]) was not statistically different between groups, at 8.42 ± 1.40 %ID in the 657 mg/kg group, 7.19 ± 0.86 %ID in the 329 mg/kg group, 8.20 ± 2.44 %ID in the 164 mg/kg group, and 8.67 ± 1.97 %ID in the PBS group. Kidney uptake was significantly lower in the 657 mg/kg group (85.8 ± 24.2 %ID) than in the 329 mg/kg (159 ± 26.2 %ID), 164 mg/kg (211 ± 27.4 %ID), and PBS groups (182 ± 33.5 %ID) (P < 0.001). Salivary gland uptake was lower in the 657 mg/kg (3.72 ± 2.12 %ID) and 329 mg/kg (5.74 ± 0.62 %ID) groups than in the PBS group (10.04 ± 2.52 %ID) (P < 0.01). Conclusion: MSG decreased salivary and kidney uptake of 68Ga-PSMA-11 in a dose-dependent manner, whereas tumor uptake was unaffected.
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Affiliation(s)
- Etienne Rousseau
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
| | - Joseph Lau
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
| | - Hsiou-Ting Kuo
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
| | - Zhengxing Zhang
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
| | - Helen Merkens
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
| | - Navjit Hundal-Jabal
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
| | - Nadine Colpo
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
| | - Kuo-Shyan Lin
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - François Bénard
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Columbia, Canada; and
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
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43
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Kuo HT, Merkens H, Zhang Z, Uribe CF, Lau J, Zhang C, Colpo N, Lin KS, Bénard F. Enhancing Treatment Efficacy of 177Lu-PSMA-617 with the Conjugation of an Albumin-Binding Motif: Preclinical Dosimetry and Endoradiotherapy Studies. Mol Pharm 2018; 15:5183-5191. [PMID: 30251544 DOI: 10.1021/acs.molpharmaceut.8b00720] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We designed and evaluated a novel albumin-binder-conjugated 177Lu-PSMA-617 derivative, 177Lu-HTK01169, with an extended blood retention time to maximize the radiation dose delivered to prostate tumors expressing prostate-specific membrane antigen (PSMA). PSMA-617 and HTK01169 that contained N-[4-( p-iodophenyl)butanoyl]-Glu as an albumin-binding motif were synthesized using the solid-phase approach. Binding affinity to PSMA was determined by in vitro competition-binding assay. 177Lu labeling was performed in acetate buffer (pH 4.5) at 90 °C for 15 min. SPECT/CT imaging, biodistribution, and endoradiotherapy studies were conducted in mice bearing PSMA-expressing LNCaP tumor xenografts. Radiation dosimetry was calculated using OLINDA software. Lu-PSMA-617 and Lu-HTK01169-bound PSMA with high affinity ( Ki values = 0.24 and 0.04 nM, respectively). SPECT imaging and biodistribution studies showed that 177Lu-PSMA-617 and 177Lu-HTK01169 were excreted mainly via the renal pathway. With fast blood clearance (0.68%ID/g at 1 h postinjection), the tumor uptake of 177Lu-PSMA-617 peaked at 1 h postinjection (15.1%ID/g) and gradually decreased to 7.91%ID/g at 120 h postinjection. With extended blood retention (16.6 and 2.10%ID/g at 1 and 24 h, respectively), the tumor uptake of 177Lu-HTK01169 peaked at 24 h postinjection (55.9%ID/g) and remained at the same level by the end of the study (120 h). Based on dosimetry calculations, 177Lu-HTK01169 delivered an 8.3-fold higher radiation dose than 177Lu-PSMA-617 to LNCaP tumor xenografts. For the endoradiotherapy study, the mice treated with 177Lu-PSMA-617 (18.5 MBq) all reached humane end point (tumor volume >1000 mm3) by Day 73 with a median survival of 58 days. Mice treated with 18.5, 9.3, 4.6, or 2.3 MBq of 177Lu-HTK01169 had a median survival of >120, 103, 61, and 28 days, respectively. With greatly enhanced tumor uptake and treatment efficacy compared to 177Lu-PSMA-617 in preclinical studies, 177Lu-HTK01169 warrants further investigation for endoradiotherapy of prostate cancer.
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Affiliation(s)
- Hsiou-Ting Kuo
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada
| | - Helen Merkens
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada
| | - Zhengxing Zhang
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada
| | - Carlos F Uribe
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada
| | - Joseph Lau
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada
| | - Chengcheng Zhang
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada
| | - Nadine Colpo
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada
| | - Kuo-Shyan Lin
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada.,Department of Functional Imaging , BC Cancer , Vancouver , BC V5Z 4E6 , Canada.,Department of Radiology , University of British Columbia , Vancouver , BC V5Z 1M9 , Canada
| | - François Bénard
- Department of Molecular Oncology , BC Cancer , Vancouver , BC V5Z 1L3 , Canada.,Department of Functional Imaging , BC Cancer , Vancouver , BC V5Z 4E6 , Canada.,Department of Radiology , University of British Columbia , Vancouver , BC V5Z 1M9 , Canada
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